compat.yaml-cpp 0.8.0/0.9.0 on openkal; openkal-ecosystem/openkal-compat labels; openkal measurement selects by change on x86_64-windows-musl; maintainer-hosted CN mirrors; a shorter README

compat.yaml-cpp 0.8.0/0.9.0 on openkal; openkal-ecosystem/openkal-compat labels; openkal measurement selects by change on x86_64-windows-musl; maintainer-hosted CN mirrors; a shorter README #453