Tests

Use u8 for type/symbol tags #17699

Job	Run time
Test mypyc suite with 32-bit Python	18m 31s
Test suite with py39-ubuntu, mypyc-compiled	16m 45s
Test suite with py311-ubuntu	9m 40s
Test suite with py310-ubuntu	10m 37s
Test suite with py312-ubuntu, mypyc-compiled	25m 29s
Test suite with py313-windows-64	23m 11s
Test suite with py313-ubuntu, mypyc-compiled	27m 55s
Test suite with py314-dev-ubuntu	25m 20s
mypyc runtime tests with py39-macos	5m 46s
Type check our own code (py39-windows-64)	2m 8s
Type check our own code (py39-ubuntu)	1m 36s
Formatting and code style with Black + ruff	1m 55s
	2h 48m 53s

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