mypy

gh-151941: Doc: fix Sphinx reference warnings in `Doc/c-api/` #22503

Job	Run time
Run mypy on Tools/build	29s
Run mypy on Tools/check-c-api-docs	29s
Run mypy on Tools/peg_generator	29s
Run mypy on Tools/cases_generator	27s
Run mypy on Lib/tomllib	31s
Run mypy on Lib/test/libregrtest	30s
Run mypy on Tools/clinic	30s
Run mypy on Lib/_pyrepl	35s
Run mypy on Tools/jit	29s
	4m 29s

Provide feedback