When I was testing OSSM-218 I encountered a case that Kiali was enabled, but it was temporarily unavailable during reconciliation, so as a result, Kiali was disabled.

It's not trivial to manually test this case, because there must occur a situation that Istio becomes ready before Kiali. What's more this PR includes proper unit test which verifies that Istio Operator will reconcile SMCP in case of Kiali unavailability, so I don't think that this case must be reproduced and manually verified.