pkgtool.sh:pkgtoolp_mirror_fetch(): skip mirroring of Git URL(s) if ${PKG_MIRRORS_GIT} specifies `skip'.
    subr.rtl/rtl_fetch.subr:rtlp_fetch_url_git(): skip attempting to use Git URL(s) mirror if ${_mirrors} specifies `skip'.
    groups/120.native_runtime.group:{ntctty,psxscl{,_strace}}:${PKG_MIRRORS_GIT}: skip mirroring.