Fix Python detection when making releases

[cschwan]

There is a mismatch between the Python versions

1. prepared by the setup-python action and
2. used by the maturin-action action

used in release.yml.

The latter finds more Python interpreters (for instance Python 3.13 was found although we didn't request it) and less (some PyPy versions are found because they aren't supported anymore, at least on some platforms). So we should find a way to force maturin to use the Python versions we select and error out if that's not possible.