Tests

add support for `mypy.toml` and `.mypy.toml` configuration files #21313

Job	Run time
Test mypyc suite with 32-bit Python	10m 12s
Test suite with py311-ubuntu	9m 1s
Test suite with py314t-ubuntu, mypyc-compiled	17m 49s
Test suite with py313-ubuntu, mypyc-compiled	14m 30s
Test suite with py310-ubuntu, mypyc-compiled	15m 23s
mypyc runtime tests with py313-macos	4m 37s
Test suite with py312-ubuntu	9m 30s
Test suite with py314-ubuntu, mypyc-compiled	16m 44s
Test suite with py314-windows-64	28m 13s
Formatting and code style with Black + ruff	1m 49s
mypyc runtime tests with py310-ubuntu	5m 55s
Type check our own code (py310-ubuntu)	1m 46s
Type check our own code (py310-windows-64)	2m 23s
Parallel tests with py314-ubuntu, mypyc-compiled	28m 49s
Parallel tests with py314-ubuntu, interpreted	24m 46s
Parallel tests with py314-windows-64, interpreted	12m 1s
	3h 23m 28s

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