mypy

gh-135953: Properly obtain main thread identifier in Gecko Collector … #20105

Job	Run time
Run mypy on Tools/build	17s
Run mypy on Lib/tomllib	19s
Run mypy on Tools/check-c-api-docs	17s
Run mypy on Tools/jit	21s
Run mypy on Tools/cases_generator	16s
Run mypy on Lib/_pyrepl	19s
Run mypy on Tools/peg_generator	17s
Run mypy on Tools/clinic	18s
Run mypy on Lib/test/libregrtest	18s
	2m 42s

Provide feedback