$ git clone -n https://src.fedoraproject.org/rpms/lensfun.git /var/lib/mock/f40-build-1292951-23380/root/chroot_tmpdir/scmroot/lensfun
Cloning into '/var/lib/mock/f40-build-1292951-23380/root/chroot_tmpdir/scmroot/lensfun'...
$ git fetch origin b661c761ff0f1f7e803c3bd02182f120618ab29a:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/lensfun
 * [new ref]         b661c761ff0f1f7e803c3bd02182f120618ab29a -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at b661c76 Use version_1 backported data snapshot