$ git clone -n https://src.fedoraproject.org/rpms/gap-pkg-recog.git /var/lib/mock/f38-build-side-42-init-devel-929793-28746/root/chroot_tmpdir/scmroot/gap-pkg-recog
Cloning into '/var/lib/mock/f38-build-side-42-init-devel-929793-28746/root/chroot_tmpdir/scmroot/gap-pkg-recog'...
$ git fetch origin ac4007b1234981e7c8447ed3255bda4e637d3065:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/gap-pkg-recog
 * [new ref]         ac4007b1234981e7c8447ed3255bda4e637d3065 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at ac4007b Use the %gap_arches macro.