$ git clone -n https://src.fedoraproject.org/rpms/itinerary.git /var/lib/mock/f40-build-1801970-24878/root/chroot_tmpdir/scmroot/itinerary
Cloning into '/var/lib/mock/f40-build-1801970-24878/root/chroot_tmpdir/scmroot/itinerary'...
$ git fetch origin 30aeef6f1e2c0b6aa94c331b43d0d86c03978a91:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/itinerary
 * [new ref]         30aeef6f1e2c0b6aa94c331b43d0d86c03978a91 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 30aeef6 Merge branch 'rawhide' into f40