$ git clone -n https://src.fedoraproject.org/rpms/xpenguins.git /var/lib/mock/f45-build-39061-731/root/chroot_tmpdir/scmroot/xpenguins
Cloning into '/var/lib/mock/f45-build-39061-731/root/chroot_tmpdir/scmroot/xpenguins'...
$ git fetch origin d94f2e0c6e17b9e01a6b1e832e1f08d96aa04ab8:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/xpenguins
 * [new ref]         d94f2e0c6e17b9e01a6b1e832e1f08d96aa04ab8 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at d94f2e0 Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild