bump python 3.9+ (#20413)

* bump python 3.9+

* [pre-commit.ci] auto fixes from pre-commit.com hooks

for more information, see https://pre-commit.ci

* --unsafe-fixes

* contextlib.AbstractContextManager

* type: ignore[misc]

* update CI

* apply fixes

* apply fixes

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Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>
Co-authored-by: Luca Antiga <luca.antiga@gmail.com>