CMake

ci: disable macos-11 #274

Job	Run time
build-llvm (ubuntu-20.04, Release)	40m 32s
build-llvm (ubuntu-latest, Release)	39m 52s
build-llvm (macos-latest, Release)	1h 10m 42s
build-llvm (windows-latest, Release)	1h 3m 52s
test-llvm-z80 (ubuntu-20.04, Release)	1m 44s
build-clang (ubuntu-20.04, Release)	37m 44s
test-llvm-z80 (ubuntu-latest, Release)	1m 47s
test-llvm	0s
build-clang (ubuntu-latest, Release)	37m 20s
test-llvm-z80 (macos-latest, Release)	6m 55s
build-clang (macos-latest, Release)	33m 33s
test-llvm-z80 (windows-latest, Release)	2m 51s
build-clang (windows-latest, Release)	36m 55s
test-clang	0s
	6h 13m 47s

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