$ git clone -n https://src.fedoraproject.org/rpms/at.git /var/lib/mock/f42-build-side-1-3583386-46888/root/chroot_tmpdir/scmroot/at
Cloning into '/var/lib/mock/f42-build-side-1-3583386-46888/root/chroot_tmpdir/scmroot/at'...
$ git fetch origin c697b4595ce1df51088a6427f1a53121ba70c673:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/at
 * [new ref]         c697b4595ce1df51088a6427f1a53121ba70c673 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at c697b45 Fix past date handling with -t option