$ git clone -n https://src.fedoraproject.org/rpms/buildah.git /var/lib/mock/f41-build-side-1-2749797-31006/root/chroot_tmpdir/scmroot/buildah
Cloning into '/var/lib/mock/f41-build-side-1-2749797-31006/root/chroot_tmpdir/scmroot/buildah'...
$ git fetch origin 68cf6e550f4555a3a3077e8a0273d0869b4cb322:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/buildah
 * [new ref]         68cf6e550f4555a3a3077e8a0273d0869b4cb322 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 68cf6e5 rebuild