* Build CPython 3.13 by default
Enable building with CPython 3.13 by default, no longer requiring prerelease_pythons flag to be set true.
* [pre-commit.ci] auto fixes from pre-commit.com hooks
for more information, see https://pre-commit.ci
* README.md: Add note about free-threaded support
* build_selector_test.py: cp313t still behind flag
Even with 3.13 being enabled by default, cp313t is still behind a flag for now.
This commit updates the test accordingly.
* fix unit tests
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Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>
Co-authored-by: mayeut <mayeut@users.noreply.github.com>
