mypy

gh-150858: fix data race while changing `qualname` of a type obje… #21850

Job	Run time
Run mypy on Tools/build	20s
Run mypy on Tools/check-c-api-docs	18s
Run mypy on Tools/jit	20s
Run mypy on Tools/clinic	22s
Run mypy on Tools/cases_generator	19s
Run mypy on Lib/test/libregrtest	21s
Run mypy on Tools/peg_generator	18s
Run mypy on Lib/tomllib	29s
Run mypy on Lib/_pyrepl	24s
	3m 11s

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