mypy

gh-151519: Check effective gid in `_test_all_chown_common` group-0 gu… #21922

Job	Run time
Run mypy on Tools/peg_generator	20s
Run mypy on Tools/cases_generator	20s
Run mypy on Lib/test/libregrtest	19s
Run mypy on Lib/tomllib	22s
Run mypy on Tools/jit	21s
Run mypy on Tools/clinic	18s
Run mypy on Lib/_pyrepl	23s
Run mypy on Tools/check-c-api-docs	18s
Run mypy on Tools/build	19s
	3m 0s

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