text: Title: TypeError: isinstance() argument 2 cannot be a parameterized generic
  Body: ## Issue
  
  Stacktrace with tox when loading plugin configuration. Based on the error displayed I believe that is not the plugin fault. The loaded configuration option is a list, like below:
  
  ```
  [ansible]
  skip =
      py3.7
      py3.8
      2.9
      2.10
      2.11
      2.12
      2.13
  ```
  
  I am still trying to fully understand this python typing issue in order to know how to avoid it.
  
  ## Environment
  
  Provide at least:
  
  - OS:
  
  <details open>
  <summary>Output of <code>pip list</code> of the host Python, where <code>tox</code> is installed</summary>
  
  ```console
  ROOT: Using a default tox.ini file with tox-ansible plugin is not recommended. Consider using a tox-ansible.ini file and specify it on the command line (`tox --ansible -c tox-ansible.ini`) to avoid unintentionally overriding the tox-ansible environment configurations.
  Traceback (most recent call last):
    File "/Users/ssbarnea/.asdf/installs/python/3.12.3/bin/tox", line 8, in <module>
      sys.exit(run())
               ^^^^^
    File "/Users/ssbarnea/.asdf/installs/python/3.12.3/lib/python3.12/site-packages/tox/run.py", line 20, in run
      result = main(sys.argv[1:] if args is None else args)
               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    File "/Users/ssbarnea/.asdf/installs/python/3.12.3/lib/python3.12/site-packages/tox/run.py", line 42, in main
      result = provision(state)
               ^^^^^^^^^^^^^^^^
    File "/Users/ssbarnea/.asdf/installs/python/3.12.3/lib/python3.12/site-packages/tox/provision.py", line 86, in provision
      MANAGER.tox_add_core_config(state.conf.core, state)
    File "/Users/ssbarnea/.asdf/installs/python/3.12.3/lib/python3.12/site-packages/tox/plugin/manager.py", line 79, in tox_add_core_config
      self.manager.hook.tox_add_core_config(core_conf=core_conf, state=state)
    File "/Users/ssbarnea/.asdf/installs/python/3.12.3/lib/python3.12/site-packages/pluggy/_hooks.py", line 513, in __call__
      return self._hookexec(self.name, self._hookimpls.copy(), kwargs, firstresult)
             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    File "/Users/ssbarnea/.asdf/installs/python/3.12.3/lib/python3.12/site-packages/pluggy/_manager.py", line 120, in _hookexec
      return self._inner_hookexec(hook_name, methods, kwargs, firstresult)
             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    File "/Users/ssbarnea/.asdf/installs/python/3.12.3/lib/python3.12/site-packages/pluggy/_callers.py", line 139, in _multicall
      raise exception.with_traceback(exception.__traceback__)
    File "/Users/ssbarnea/.asdf/installs/python/3.12.3/lib/python3.12/site-packages/pluggy/_callers.py", line 103, in _multicall
      res = hook_impl.function(*args)
            ^^^^^^^^^^^^^^^^^^^^^^^^^
    File "/Users/ssbarnea/c/a/tox-ansible/src/tox_ansible/plugin.py", line 168, in tox_add_core_config
      env_list = add_ansible_matrix(state)
                 ^^^^^^^^^^^^^^^^^^^^^^^^^
    File "/Users/ssbarnea/c/a/tox-ansible/src/tox_ansible/plugin.py", line 266, in add_ansible_matrix
      env for env in env_list.envs if all(skip not in env for skip in ansible_config["skip"])
                                                                      ~~~~~~~~~~~~~~^^^^^^^^
    File "/Users/ssbarnea/.asdf/installs/python/3.12.3/lib/python3.12/site-packages/tox/config/sets.py", line 116, in __getitem__
      return self.load(item)
             ^^^^^^^^^^^^^^^
    File "/Users/ssbarnea/.asdf/installs/python/3.12.3/lib/python3.12/site-packages/tox/config/sets.py", line 127, in load
      return config_definition.__call__(self._conf, self.loaders, ConfigLoadArgs(chain, self.name, self.env_name))  # noqa: PLC2801
             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    File "/Users/ssbarnea/.asdf/installs/python/3.12.3/lib/python3.12/site-packages/tox/config/of_type.py", line 103, in __call__
      value = loader.load(key, self.of_type, self.factory, conf, args)
              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    File "/Users/ssbarnea/.asdf/installs/python/3.12.3/lib/python3.12/site-packages/tox/config/loader/api.py", line 144, in load
      converted = self.build(key, of_type, factory, conf, raw, args)
                  ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    File "/Users/ssbarnea/.asdf/installs/python/3.12.3/lib/python3.12/site-packages/tox/config/loader/ini/__init__.py", line 85, in build
      converted = self.to(prepared, of_type, factory)
                  ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    File "/Users/ssbarnea/.asdf/installs/python/3.12.3/lib/python3.12/site-packages/tox/config/loader/convert.py", line 42, in to
      if isinstance(raw, of_type):  # already target type no need to transform it
         ^^^^^^^^^^^^^^^^^^^^^^^^
  TypeError: isinstance() argument 2 cannot be a parameterized generic```
  
  </details>
  
  ## Output of running tox
  
  <details open>
  <summary>Output of <code>tox -rvv</code></summary>
  
  ```console
  
  ```
  
  </details>
  
  ## Minimal example
  
  <!--  If possible, provide a minimal reproducer for the issue. -->
  
  ```console
  
  ```
  
  https://github.com/ansible-collections/cisco.nxos/actions/runs/9277917412/job/25528009504
  
  