mypy

gh-145883: Fix two heap-buffer-overflows in `_zoneinfo` #20285

Job	Run time
Run mypy on Tools/cases_generator	19s
Run mypy on Lib/_pyrepl	21s
Run mypy on Tools/check-c-api-docs	18s
Run mypy on Tools/peg_generator	17s
Run mypy on Tools/build	19s
Run mypy on Lib/tomllib	17s
Run mypy on Tools/jit	20s
Run mypy on Lib/test/libregrtest	20s
Run mypy on Tools/clinic	21s
	2m 52s

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