mypy

Get rid of `ERROR_IF`'s "label" parameter #14124

Job	Run time
Run mypy on Lib/_pyrepl	14s
Run mypy on Lib/test/libregrtest	19s
Run mypy on Tools/build	14s
Run mypy on Tools/cases_generator	14s
Run mypy on Tools/clinic	18s
Run mypy on Tools/jit	17s
Run mypy on Tools/peg_generator	19s
Run mypy on Tools/wasm	16s
	2m 11s

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