$ git clone -n https://src.fedoraproject.org/rpms/buildbox.git /var/lib/mock/f41-build-840195-160595/root/chroot_tmpdir/scmroot/buildbox
Cloning into '/var/lib/mock/f41-build-840195-160595/root/chroot_tmpdir/scmroot/buildbox'...
$ git fetch origin 427e4e110f6a198aa74191730cd15c2be4ba598b:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/buildbox
 * [new ref]         427e4e110f6a198aa74191730cd15c2be4ba598b -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 427e4e1 Update to 1.2.13