mypy

gh-151424: Fix impossible stack traces in `RemoteUnwinder(..., cache_… #21887

Job	Run time
Run mypy on Tools/jit	21s
Run mypy on Tools/build	17s
Run mypy on Tools/check-c-api-docs	20s
Run mypy on Tools/peg_generator	17s
Run mypy on Lib/_pyrepl	17s
Run mypy on Lib/test/libregrtest	22s
Run mypy on Tools/cases_generator	17s
Run mypy on Lib/tomllib	19s
Run mypy on Tools/clinic	19s
	2m 49s

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