$ git clone -n https://src.fedoraproject.org/rpms/openarc.git /var/lib/mock/f45-build-20974-576/root/chroot_tmpdir/scmroot/openarc
Cloning into '/var/lib/mock/f45-build-20974-576/root/chroot_tmpdir/scmroot/openarc'...
$ git fetch origin 63e7a84cade159ac35913a958e84314b3c8ad0c7:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/openarc
 * [new ref]         63e7a84cade159ac35913a958e84314b3c8ad0c7 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 63e7a84 Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild