Knative Serving goes into active even if the Knative Operator fails to create a serving instance

[ca-scribner]

If we provide incorrect configuration to knative serving, the charm still "installs" (creates a CRD) successfully and goes to active even though serving is not installed and working. This can be seen by doing:

juju add-model kubeflow

juju deploy istio-pilot --trust --channel 1.11/stable --config default-gateway=my-gateway
juju deploy istio-gateway istio-ingressgateway --trust --channel 1.11/stable --config kind=ingress
juju relate istio-pilot istio-ingressgateway

juju deploy knative-operator --trust --channel latest/edge
juju deploy knative-serving --trust --channel latest/edge --config namespace=knative-serving --config istio.gateway.name=my-gateway --config istio.gateway.namespace=not-kubeflow # <------------------incorrect gateway namespace

knative serving will go into active, but if we kubectl describe knativeserving -n knative-serving -o yaml we will see the install is incomplete. Our charm could do something similar, checking for this to be completed before saying it is active