$ git clone -n https://src.fedoraproject.org/rpms/redis.git /var/lib/mock/f39-build-1489846-34502/root/chroot_tmpdir/scmroot/redis
Cloning into '/var/lib/mock/f39-build-1489846-34502/root/chroot_tmpdir/scmroot/redis'...
$ git fetch origin 2fd96b84ea2d454469646447b89c8c239e69bb45:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/redis
 * [new ref]         2fd96b84ea2d454469646447b89c8c239e69bb45 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 2fd96b8 refresh doc