CI: Require Python >= 3.13.5

[hugovk]

Summary of changes

Some Windows jobs are failing because it's Python 3.13.4, which incorrectly tries to link to the threaded version. See python/cpython#135151.

This has been fixed in last week's 3.13.5 release, but it's not necessarily in the default CI images yet, so let's specify >= 3.13.5 to ensure the new one is always installed on-demand.

This can be reverted at some point in the future.

Closes #5037.

Pull Request Checklist

• Changes have tests
• [n/a] News fragment added in newsfragments/.
  (See documentation for details)

[Avasam]

I think https://github.com/actions/setup-python/blob/main/docs/advanced-usage.md#check-latest-version is also an option.

[hugovk]

Yeah, although this would affect all of 3.9-3.14 and PyPy:

Setting check-latest to true impacts performance as downloading Python or PyPy versions is slower than using cached versions.

But happy to change if you like, it might not make much difference either way.

[abravalheri]

Thank you very much @hugovk.

I think we can accept this as a temporary change until 3.13.5 or bigger becomes the default version installed in the GHA worker.

This is because usually this part of the CI configuration is managed externally on jaraco/skeleton.

I think we can add a note clarifying that so that future conflict merges with jaraco/skeleton become easy to resolve.

[abravalheri]

Thank you very much.