NetworkManager credentials aren't marked as invalid ever

[agrare]

If we cannot authenticate to the OVN API we do not mark the credentials as invalid so refresh and event catcher tries to run constantly. Specifically the Redhat::NetworkManager::EventCatcher restarts every 15 seconds constantly dumping errors to the logs.

This is because the authentication_status is delegated to the parent manager:
https://github.com/ManageIQ/manageiq-providers-ovirt/blob/master/app/models/manageiq/providers/redhat/network_manager.rb#L25-L30

We should at least be checking the status against the network manager API even if we use the parent_manager's authentications