WHY
Because addon-flow installation might get stuck if pagerduty secret is not created by OCM/Hive quick enough

WHAT
Pagerduty secret is created by OCM/Hive so there can be a several minutes delay between RHOAM installation start and pagerduty secret creation.

The issue is that it the secret is not fount (because OCM/Hive haven't created it yet) RHMI controller reconcile is not properly requeued. An empty result and nil error are returned:
https://github.com/integr8ly/integreatly-operator/blob/master/controllers/rhmi/rhmi_controller.go#L988-L1009

Workaround: restart rhoam operator (delete the pod)

HOW
Return this non-empty result instead to requeue:
https://github.com/integr8ly/integreatly-operator/blob/master/controllers/rhmi/rhmi_controller.go#L953-L956

TESTS
Some unit/efe tests to cover missing secret scenario potentially

DONE

• rhoam install does not stuck if pagerduty secret does not exist
• it reques the preflight checks properly so that once the secret appears the rhoam install is unblocked and continues