mypy

gh-130168: pyrepl can messup and poll is not thread safe #16937

Job	Run time
Run mypy on Tools/cases_generator	17s
Run mypy on Tools/build	16s
Run mypy on Tools/peg_generator	21s
Run mypy on Tools/clinic	18s
Run mypy on Lib/test/libregrtest	17s
Run mypy on Lib/tomllib	16s
Run mypy on Tools/jit	16s
Run mypy on Lib/_pyrepl	16s
	2m 17s

Provide feedback