Use flaky pytest fixture instead of decorator

[mgorny]

Replace the direct use of flaky.flaky decorator with the equivalent pytest fixture. This is both more canonical, and has the additional advantage of being compatible with the more modern pytest-rerunfailures plugin, that can be used in place of flaky.

Fixes #2003

[nedbat]

Thanks. We can remove it from the requirements.in file (https://github.com/nedbat/coveragepy/blob/master/requirements/pytest.in#L9) too. make upgrade should rebuild the .txt files.

[nedbat]

I can handle the requirements later if you want. But why can't I find docs for pytest.mark.flaky?

[mgorny]

I think there's a slight misunderstand. pytest.mark.flaky is provided both by flaky and pytest-rerunfailures packages:

• https://github.com/box/flaky?tab=readme-ov-file#pytest-marker
• https://pypi.org/project/pytest-rerunfailures/#re-run-individual-failures

For a minimal change, I've left it at flaky. If you want, I can swap it for pytest-rerunfailures — it's a matter of replacing the dep and removign --no-flaky-report (pytest-rerunfailures doesn't do such a thing).

[nedbat]

You're right, I did misunderstand. OK, let's make this change and keep pushing forward.

[mgorny]

Thanks!