Fix matching against union of tuples #17089

Job	Run time
Test mypyc suite with 32-bit Python	8m 6s
Test suite with py310-ubuntu	12m 6s
Test suite with py314-dev-ubuntu	16m 9s
Test suite with py39-ubuntu, mypyc-compiled	14m 17s
Test suite with py312-ubuntu, mypyc-compiled	13m 10s
Type check our own code (py39-ubuntu)	1m 37s
Test suite with py311-ubuntu	9m 21s
Test suite with py313-windows-64	22m 26s
Type check our own code (py39-windows-64)	2m 29s
Test suite with py313-ubuntu, mypyc-compiled	13m 34s
Formatting and code style with Black + ruff	1m 47s
mypyc runtime tests with py39-macos	4m 38s
	1h 59m 40s

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