$ git clone -n https://src.fedoraproject.org/rpms/rubygem-pango.git /var/lib/mock/f40-build-733959-105598/root/chroot_tmpdir/scmroot/rubygem-pango
Cloning into '/var/lib/mock/f40-build-733959-105598/root/chroot_tmpdir/scmroot/rubygem-pango'...
$ git fetch origin e840041880e0aa5fdee5c96117550ba1db92a5cc:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rubygem-pango
 * [new ref]         e840041880e0aa5fdee5c96117550ba1db92a5cc -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at e840041 4.2.0 entry