$ git clone -n https://src.fedoraproject.org/rpms/gxkb.git /var/lib/mock/f40-build-788442-135157/root/chroot_tmpdir/scmroot/gxkb
Cloning into '/var/lib/mock/f40-build-788442-135157/root/chroot_tmpdir/scmroot/gxkb'...
$ git fetch origin 6c0cb0ab3764336933bbaa160db0eefab390d07d:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/gxkb
 * [new ref]         6c0cb0ab3764336933bbaa160db0eefab390d07d -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 6c0cb0a [packit] 0.9.5 upstream release