$ git clone -n https://src.fedoraproject.org/rpms/arpwatch.git /var/lib/mock/f41-build-side-1-2844833-33879/root/chroot_tmpdir/scmroot/arpwatch
Cloning into '/var/lib/mock/f41-build-side-1-2844833-33879/root/chroot_tmpdir/scmroot/arpwatch'...
$ git fetch origin 166eb3112073da7fca06af00c9de05a54755c69e:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/arpwatch
 * [new ref]         166eb3112073da7fca06af00c9de05a54755c69e -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 166eb31 Update to 3.7 (close RHBZ#2316380)