[Upgrade] Stabilize OVN upgrade CI so that it can be signal for upgrade graph updates

With OVN planning to be default in 4.9 we need to ensure that upgrade graphs are not updated
if there are issues with upgrading with an OVN deployment.

upgrade jobs need to be run as a blocking job for CI and nightly payloads that can be seen here

also, we need to make sure that an ovn deployment upgrade job is run for the release path like we see happening
here