ci: Set ZIG_GLOBAL_CACHE_DIR and ZIG_LOCAL_CACHE_DIR earlier.
Otherwise the disk just keeps getting filled up.
Also remove some pointless cleanup commands since the actions/checkout workflow
step already cleans the repository by default.
1cbfdb4244Alex Rønne Petersen committed on 1/29/2025, 7:46:53 PM· committed by Andrew Kelleyparent798bb0b