$ git clone -n https://src.fedoraproject.org/rpms/rubygem-aruba.git /var/lib/mock/f41-build-717228-13077/root/chroot_tmpdir/scmroot/rubygem-aruba
Cloning into '/var/lib/mock/f41-build-717228-13077/root/chroot_tmpdir/scmroot/rubygem-aruba'...
$ git fetch origin eb630ff8873ec95157a52193c818b78288880f47:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rubygem-aruba
 * [new ref]         eb630ff8873ec95157a52193c818b78288880f47 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at eb630ff add upstream bug reference