$ git clone -n https://src.fedoraproject.org/rpms/jackson-dataformats-binary.git /var/lib/mock/f40-build-2686431-68061/root/chroot_tmpdir/scmroot/jackson-dataformats-binary
Cloning into '/var/lib/mock/f40-build-2686431-68061/root/chroot_tmpdir/scmroot/jackson-dataformats-binary'...
$ git fetch origin 2981635d9126b2db144e08429c5640f16fa0181d:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/jackson-dataformats-binary
 * [new ref]         2981635d9126b2db144e08429c5640f16fa0181d -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 2981635 Retired: Long term failure to build