$ git clone -n https://src.fedoraproject.org/rpms/kf6-kfilemetadata.git /var/lib/mock/f42-build-3350035-45010/root/chroot_tmpdir/scmroot/kf6-kfilemetadata
Cloning into '/var/lib/mock/f42-build-3350035-45010/root/chroot_tmpdir/scmroot/kf6-kfilemetadata'...
$ git fetch origin b55c62dad5a3e341c26a88aad154b6bffd8fb97a:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/kf6-kfilemetadata
 * [new ref]         b55c62dad5a3e341c26a88aad154b6bffd8fb97a -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at b55c62d 6.12.0