$ git clone -n https://src.fedoraproject.org/rpms/filelight.git /var/lib/mock/f42-build-side-1-3506315-45996/root/chroot_tmpdir/scmroot/filelight
Cloning into '/var/lib/mock/f42-build-side-1-3506315-45996/root/chroot_tmpdir/scmroot/filelight'...
$ git fetch origin b4a1f03f96150c388d1754db4473e0f99b1fe33d:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/filelight
 * [new ref]         b4a1f03f96150c388d1754db4473e0f99b1fe33d -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at b4a1f03 25.04.0