$ git clone -n https://src.fedoraproject.org/rpms/mtr.git /var/lib/mock/f41-build-1273218-23132/root/chroot_tmpdir/scmroot/mtr
Cloning into '/var/lib/mock/f41-build-1273218-23132/root/chroot_tmpdir/scmroot/mtr'...
$ git fetch origin 92ec0a47fe6cc56541b9df48bfa6b7a0b5ee7d5c:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/mtr
 * [new ref]         92ec0a47fe6cc56541b9df48bfa6b7a0b5ee7d5c -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 92ec0a4 Eliminate use of obsolete %patchN syntax (#2283636)