$ git clone -n https://src.fedoraproject.org/rpms/rubygem-clutter-gdk.git /var/lib/mock/f42-build-side-115087-61059186-6588325/root/chroot_tmpdir/scmroot/rubygem-clutter-gdk
Cloning into '/var/lib/mock/f42-build-side-115087-61059186-6588325/root/chroot_tmpdir/scmroot/rubygem-clutter-gdk'...
$ git fetch origin 2d0a2e874a247045e424516e0676fd7e1b20b8e2:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rubygem-clutter-gdk
 * [new ref]         2d0a2e874a247045e424516e0676fd7e1b20b8e2 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 2d0a2e8 4.3.0 entry