When the k8s cluster is created in a private network without
FIP and without a LB FIP, the cluster is not reachable by Magnum
control plane. For this case, the cluster health status is unknown
for Magnum and Magnum should not connect the cluster to avoid
unnecessary logs.
Task: 36187
Story: 2006383
Change-Id: Ibb589ec51f91f05a334c907560ef5fe57cbfbffb