With [1] default Neutron backend set by Devstack is changed to OVN.
So now most of the Tobiko jobs are running on the Neutron with ML2/OVN
backend.
Jobs which were before "-ovn" jobs are now changed to the "-ovs" jobs
and runs ML2/OVS backend in Neutron.
Additionally this patch switched devstack-tobiko-gate-octavia job to be
run with ML2/OVS backend in Neutron.
Jobs devstack-tobiko-faults and devstack-tobiko-gate-multinode are
for now explicitly set to be run on ML2/OVS backend as some tests are
failing in those multinode jobs while running on OVN and that needs
further investigation.
[1] https://review.opendev.org/c/openstack/devstack/+/791436
Change-Id: Iefc255a33d3da509b31d93f13c771357d2ef5fa7
3a5d5a3bb7