text: Title: Segmentation Fault - wait_signal.wait & _WaitWidgetContextManager.__exit__
  Body: Hi,
  
  With python 3.8 I am getting a segmentation fault at some wait functions when using macOS and WIndows. I could not reproduce it with Linux.
  With Python 3.7 and 2.7 everything works fine for all OS flavors.
  
  ## Versions:
  OS: macOS 10.14.6
  Qt: 5.12.5 (conda-forge)
  PyQt: 5.12.3 (conda-forge)
  pytest-qt: master
  pytest: 5.4.1 (conda-forge)
  
  ## Stacktrace - wait_signal.wait
  For this particular test I am using `qtbot.waitSignal`.
  
  ```
  Fatal Python error: Segmentation fault
  
  Current thread 0x00000001098155c0 (most recent call first):
    File "/Users/slepicka/mc/envs/py38/lib/python3.8/site-packages/pytestqt/wait_signal.py", line 51 in wait
    File "/Users/slepicka/sandbox/git-slaclab/pydm-git/pydm/tests/widgets/test_rules.py", line 97 in test_rules_full
    File "/Users/slepicka/mc/envs/py38/lib/python3.8/site-packages/_pytest/python.py", line 184 in pytest_pyfunc_call
    File "/Users/slepicka/mc/envs/py38/lib/python3.8/site-packages/pluggy/callers.py", line 187 in _multicall
    File "/Users/slepicka/mc/envs/py38/lib/python3.8/site-packages/pluggy/manager.py", line 84 in <lambda>
    File "/Users/slepicka/mc/envs/py38/lib/python3.8/site-packages/pluggy/manager.py", line 93 in _hookexec
    File "/Users/slepicka/mc/envs/py38/lib/python3.8/site-packages/pluggy/hooks.py", line 286 in __call__
    File "/Users/slepicka/mc/envs/py38/lib/python3.8/site-packages/_pytest/python.py", line 1479 in runtest
    File "/Users/slepicka/mc/envs/py38/lib/python3.8/site-packages/_pytest/runner.py", line 135 in pytest_runtest_call
    File "/Users/slepicka/mc/envs/py38/lib/python3.8/site-packages/pluggy/callers.py", line 187 in _multicall
    File "/Users/slepicka/mc/envs/py38/lib/python3.8/site-packages/pluggy/manager.py", line 84 in <lambda>
    File "/Users/slepicka/mc/envs/py38/lib/python3.8/site-packages/pluggy/manager.py", line 93 in _hookexec
    File "/Users/slepicka/mc/envs/py38/lib/python3.8/site-packages/pluggy/hooks.py", line 286 in __call__
    File "/Users/slepicka/mc/envs/py38/lib/python3.8/site-packages/_pytest/runner.py", line 217 in <lambda>
    File "/Users/slepicka/mc/envs/py38/lib/python3.8/site-packages/_pytest/runner.py", line 244 in from_call
    File "/Users/slepicka/mc/envs/py38/lib/python3.8/site-packages/_pytest/runner.py", line 216 in call_runtest_hook
    File "/Users/slepicka/mc/envs/py38/lib/python3.8/site-packages/_pytest/runner.py", line 186 in call_and_report
    File "/Users/slepicka/mc/envs/py38/lib/python3.8/site-packages/_pytest/runner.py", line 100 in runtestprotocol
    File "/Users/slepicka/mc/envs/py38/lib/python3.8/site-packages/_pytest/runner.py", line 85 in pytest_runtest_protocol
    File "/Users/slepicka/mc/envs/py38/lib/python3.8/site-packages/pluggy/callers.py", line 187 in _multicall
    File "/Users/slepicka/mc/envs/py38/lib/python3.8/site-packages/pluggy/manager.py", line 84 in <lambda>
    File "/Users/slepicka/mc/envs/py38/lib/python3.8/site-packages/pluggy/manager.py", line 93 in _hookexec
    File "/Users/slepicka/mc/envs/py38/lib/python3.8/site-packages/pluggy/hooks.py", line 286 in __call__
    File "/Users/slepicka/mc/envs/py38/lib/python3.8/site-packages/_pytest/main.py", line 272 in pytest_runtestloop
    File "/Users/slepicka/mc/envs/py38/lib/python3.8/site-packages/pluggy/callers.py", line 187 in _multicall
    File "/Users/slepicka/mc/envs/py38/lib/python3.8/site-packages/pluggy/manager.py", line 84 in <lambda>
    File "/Users/slepicka/mc/envs/py38/lib/python3.8/site-packages/pluggy/manager.py", line 93 in _hookexec
    File "/Users/slepicka/mc/envs/py38/lib/python3.8/site-packages/pluggy/hooks.py", line 286 in __call__
    File "/Users/slepicka/mc/envs/py38/lib/python3.8/site-packages/_pytest/main.py", line 247 in _main
    File "/Users/slepicka/mc/envs/py38/lib/python3.8/site-packages/_pytest/main.py", line 191 in wrap_session
    File "/Users/slepicka/mc/envs/py38/lib/python3.8/site-packages/_pytest/main.py", line 240 in pytest_cmdline_main
    File "/Users/slepicka/mc/envs/py38/lib/python3.8/site-packages/pluggy/callers.py", line 187 in _multicall
    File "/Users/slepicka/mc/envs/py38/lib/python3.8/site-packages/pluggy/manager.py", line 84 in <lambda>
    File "/Users/slepicka/mc/envs/py38/lib/python3.8/site-packages/pluggy/manager.py", line 93 in _hookexec
    File "/Users/slepicka/mc/envs/py38/lib/python3.8/site-packages/pluggy/hooks.py", line 286 in __call__
    File "/Users/slepicka/mc/envs/py38/lib/python3.8/site-packages/_pytest/config/__init__.py", line 124 in main
    File "run_tests.py", line 21 in <module>
  Segmentation fault: 11
  ```
  
  ## Stacktrace.- _WaitWidgetContextManager.__exit__
  
  In this case my test was using `qtbot.waitExposed`.
  
  ```
  Current thread 0x000000010f0e35c0 (most recent call first):
    File "/usr/local/miniconda/envs/test-environment-3.8/lib/python3.8/site-packages/pytestqt/qtbot.py", line 723 in __exit__
    File "/Users/runner/runners/2.165.2/work/1/s/pydm/tests/widgets/test_drawing.py", line 508 in test_pydmdrawingline_draw_item
    File "/usr/local/miniconda/envs/test-environment-3.8/lib/python3.8/site-packages/_pytest/python.py", line 184 in pytest_pyfunc_call
    File "/usr/local/miniconda/envs/test-environment-3.8/lib/python3.8/site-packages/pluggy/callers.py", line 187 in _multicall
    File "/usr/local/miniconda/envs/test-environment-3.8/lib/python3.8/site-packages/pluggy/manager.py", line 84 in <lambda>
    File "/usr/local/miniconda/envs/test-environment-3.8/lib/python3.8/site-packages/pluggy/manager.py", line 93 in _hookexec
    File "/usr/local/miniconda/envs/test-environment-3.8/lib/python3.8/site-packages/pluggy/hooks.py", line 286 in __call__
    File "/usr/local/miniconda/envs/test-environment-3.8/lib/python3.8/site-packages/_pytest/python.py", line 1479 in runtest
    File "/usr/local/miniconda/envs/test-environment-3.8/lib/python3.8/site-packages/_pytest/runner.py", line 135 in pytest_runtest_call
    File "/usr/local/miniconda/envs/test-environment-3.8/lib/python3.8/site-packages/pluggy/callers.py", line 187 in _multicall
    File "/usr/local/miniconda/envs/test-environment-3.8/lib/python3.8/site-packages/pluggy/manager.py", line 84 in <lambda>
    File "/usr/local/miniconda/envs/test-environment-3.8/lib/python3.8/site-packages/pluggy/manager.py", line 93 in _hookexec
    File "/usr/local/miniconda/envs/test-environment-3.8/lib/python3.8/site-packages/pluggy/hooks.py", line 286 in __call__
    File "/usr/local/miniconda/envs/test-environment-3.8/lib/python3.8/site-packages/_pytest/runner.py", line 217 in <lambda>
    File "/usr/local/miniconda/envs/test-environment-3.8/lib/python3.8/site-packages/_pytest/runner.py", line 244 in from_call
    File "/usr/local/miniconda/envs/test-environment-3.8/lib/python3.8/site-packages/_pytest/runner.py", line 216 in call_runtest_hook
    File "/usr/local/miniconda/envs/test-environment-3.8/lib/python3.8/site-packages/_pytest/runner.py", line 186 in call_and_report
    File "/usr/local/miniconda/envs/test-environment-3.8/lib/python3.8/site-packages/_pytest/runner.py", line 100 in runtestprotocol
    File "/usr/local/miniconda/envs/test-environment-3.8/lib/python3.8/site-packages/_pytest/runner.py", line 85 in pytest_runtest_protocol
    File "/usr/local/miniconda/envs/test-environment-3.8/lib/python3.8/site-packages/pluggy/callers.py", line 187 in _multicall
    File "/usr/local/miniconda/envs/test-environment-3.8/lib/python3.8/site-packages/pluggy/manager.py", line 84 in <lambda>
    File "/usr/local/miniconda/envs/test-environment-3.8/lib/python3.8/site-packages/pluggy/manager.py", line 93 in _hookexec
    File "/usr/local/miniconda/envs/test-environment-3.8/lib/python3.8/site-packages/pluggy/hooks.py", line 286 in __call__
    File "/usr/local/miniconda/envs/test-environment-3.8/lib/python3.8/site-packages/_pytest/main.py", line 272 in pytest_runtestloop
    File "/usr/local/miniconda/envs/test-environment-3.8/lib/python3.8/site-packages/pluggy/callers.py", line 187 in _multicall
    File "/usr/local/miniconda/envs/test-environment-3.8/lib/python3.8/site-packages/pluggy/manager.py", line 84 in <lambda>
    File "/usr/local/miniconda/envs/test-environment-3.8/lib/python3.8/site-packages/pluggy/manager.py", line 93 in _hookexec
    File "/usr/local/miniconda/envs/test-environment-3.8/lib/python3.8/site-packages/pluggy/hooks.py", line 286 in __call__
    File "/usr/local/miniconda/envs/test-environment-3.8/lib/python3.8/site-packages/_pytest/main.py", line 247 in _main
    File "/usr/local/miniconda/envs/test-environment-3.8/lib/python3.8/site-packages/_pytest/main.py", line 191 in wrap_session
    File "/usr/local/miniconda/envs/test-environment-3.8/lib/python3.8/site-packages/_pytest/main.py", line 240 in pytest_cmdline_main
    File "/usr/local/miniconda/envs/test-environment-3.8/lib/python3.8/site-packages/pluggy/callers.py", line 187 in _multicall
    File "/usr/local/miniconda/envs/test-environment-3.8/lib/python3.8/site-packages/pluggy/manager.py", line 84 in <lambda>
    File "/usr/local/miniconda/envs/test-environment-3.8/lib/python3.8/site-packages/pluggy/manager.py", line 93 in _hookexec
    File "/usr/local/miniconda/envs/test-environment-3.8/lib/python3.8/site-packages/pluggy/hooks.py", line 286 in __call__
    File "/usr/local/miniconda/envs/test-environment-3.8/lib/python3.8/site-packages/_pytest/config/__init__.py", line 124 in main
    File "run_tests.py", line 21 in <module>
  /Users/runner/runners/2.165.2/work/_temp/7e5f89e4-e30b-455e-83d2-e2695b1f105e.sh: line 2:   955 Segmentation fault: 11 
  ```