text: Title: waitUntil page should link to waitUntil API doc and/or demonstrate use of the timeout param
  Body: Thanks for pytest-qt, it is a fantastic plugin. 😊 
  
  This is mostly a to-do-eventually for me, but writing it down in case someone else can pick it up earlier.
  
  I was wanting to figure out whether waitUntil had a timeout parameter, but the top result on DDG is the [waitUntil tutorial/demo page](https://pytest-qt.readthedocs.io/en/latest/wait_until.html) ([source](https://github.com/pytest-dev/pytest-qt/blob/6026f8bac834fd1a78776a4326dd27691e89b286/docs/wait_until.rst)), which does not use the `timeout=` kwarg and does not link out to the [API reference page](https://pytest-qt.readthedocs.io/en/latest/reference.html#pytestqt.qtbot.QtBot.waitUntil) ([source](https://github.com/pytest-dev/pytest-qt/blob/6026f8bac834fd1a78776a4326dd27691e89b286/src/pytestqt/qtbot.py#L483-L552)).
  
  Not a big deal, but either of those would have saved me a search. 😊 
  
  Thanks again!