$ git clone -n https://src.fedoraproject.org/rpms/mmlib.git /var/lib/mock/f38-build-side-42-init-devel-725378-27318/root/chroot_tmpdir/scmroot/mmlib
Cloning into '/var/lib/mock/f38-build-side-42-init-devel-725378-27318/root/chroot_tmpdir/scmroot/mmlib'...
$ git fetch origin ebe00d6d738689b3f5665ea2c9d88decbc20d9b6:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/mmlib
 * [new ref]         ebe00d6d738689b3f5665ea2c9d88decbc20d9b6 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at ebe00d6 Initial package (close RHBZ#2178190)