$ git clone -n https://src.fedoraproject.org/rpms/massif-visualizer.git /var/lib/mock/eln-build-side-115125-61061779-6588366/root/chroot_tmpdir/scmroot/massif-visualizer
Cloning into '/var/lib/mock/eln-build-side-115125-61061779-6588366/root/chroot_tmpdir/scmroot/massif-visualizer'...
$ git fetch origin 8d570d6580571524c751c5a0c460db8e2aaa2b28:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/massif-visualizer
 * [new ref]         8d570d6580571524c751c5a0c460db8e2aaa2b28 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 8d570d6 25.07.80