feat(checker): add musl #8796

Job	Run time
Documentation	1m 3s
Linux tests (3.10)	6m 25s
Linux tests (3.9)	7m 47s
Linux tests (3.11)	6m 25s
Long tests on Python 3.13	12m 31s
Linux tests (3.12)	6m 15s
Long tests on Python 3.13 (language parsers)	5m 2s
Tests that may fail due to network or HTML	3m 6s
Long tests on Python 3.13 (synchronous)	3m 31s
Long tests on Python 3.13 (scanners)	45m 41s
Windows long tests	1h 8m 15s
	2h 46m 1s

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