mypy

gh-135386: Fix "unable to open database file" errors on readonly DB (… #9511

Job	Run time
Run mypy on Lib/_pyrepl	19s
Run mypy on Lib/test/libregrtest	19s
Run mypy on Tools/build	16s
Run mypy on Lib/tomllib	21s
Run mypy on Tools/cases_generator	15s
Run mypy on Tools/peg_generator	18s
Run mypy on Tools/clinic	15s
Run mypy on Tools/jit	20s
	2m 23s

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