$ git clone -n https://src.fedoraproject.org/rpms/rpkg.git /var/lib/mock/f41-build-1189069-22177/root/chroot_tmpdir/scmroot/rpkg
Cloning into '/var/lib/mock/f41-build-1189069-22177/root/chroot_tmpdir/scmroot/rpkg'...
$ git fetch origin 8a987032d1675375f57417d2b7b255d8fdb815a1:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rpkg
 * [new ref]         8a987032d1675375f57417d2b7b255d8fdb815a1 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 8a98703 New release 1.67