$ git clone -n https://src.fedoraproject.org/rpms/vnstat.git /var/lib/mock/f41-build-725978-13125/root/chroot_tmpdir/scmroot/vnstat
Cloning into '/var/lib/mock/f41-build-725978-13125/root/chroot_tmpdir/scmroot/vnstat'...
$ git fetch origin 0cad8487c3d8b394bec98c5e7f9a6f75b2880697:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/vnstat
 * [new ref]         0cad8487c3d8b394bec98c5e7f9a6f75b2880697 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 0cad848 Eliminate use of obsolete %patchN syntax (#2283636)