8645: pytest.warns(None) is now deprecated because many people used
it to mean “this code does not emit warnings”, but it actually had the
effect of checking that the code emits at least one warning of any
type-like pytest.warns() or pytest.warns(Warning)
With Pytest 7:
https://docs.pytest.org/en/stable/changelog.html#pytest-7-0-0rc1-2021-12-06
With Pytest 8 it's the error.
Changed according to the documentation: https://docs.pytest.org/en/latest/how-to/capture-warnings.html#additional-use-cases-of-warnings-in-tests
Fixes: https://github.com/PyCQA/isort/issues/2234