$ git clone -n https://src.fedoraproject.org/rpms/snapshot.git /var/lib/mock/f42-build-side-1-3589326-46957/root/chroot_tmpdir/scmroot/snapshot
Cloning into '/var/lib/mock/f42-build-side-1-3589326-46957/root/chroot_tmpdir/scmroot/snapshot'...
$ git fetch origin 630da56915a889480eb0fba1392786336f80ded5:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/snapshot
 * [new ref]         630da56915a889480eb0fba1392786336f80ded5 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 630da56 Update to version 48.0.1; Fixes RHBZ#2332394