$ git clone -n https://src.fedoraproject.org/rpms/group-service.git /var/lib/mock/f45-build-13035-446/root/chroot_tmpdir/scmroot/group-service
Cloning into '/var/lib/mock/f45-build-13035-446/root/chroot_tmpdir/scmroot/group-service'...
$ git fetch origin eec3b105dd1735cccdda65491a0e699b70ca0121:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/group-service
 * [new ref]         eec3b105dd1735cccdda65491a0e699b70ca0121 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at eec3b10 Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild