$ git clone -n https://src.fedoraproject.org/rpms/vdo.git /var/lib/mock/f42-build-880038-182393/root/chroot_tmpdir/scmroot/vdo
Cloning into '/var/lib/mock/f42-build-880038-182393/root/chroot_tmpdir/scmroot/vdo'...
$ git fetch origin 887201fd8017193c511804aff8dd7577ea0a79a1:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/vdo
 * [new ref]         887201fd8017193c511804aff8dd7577ea0a79a1 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 887201f Update to 8.3.0.73 (rhbz#2342887)