✨ Handle Kubernetes events for waiting CoreProvider in preflight check

[dmvolod]

What this PR does / why we need it:
This PR allows you to avoid from polling in reconcile loop every 30 seconds, and move to catching events from the CoreProvider object when Ready condition become True. We should avoid re-querying at intervals where possible.

Also, configSecret request is optimized if option is enabled. Since a cluster can have a large number of secret objects, it is a very expensive procedure to go through all the providers each time secrets are catches without an index. The number of provider objects in the cluster is small enough that the index on the name/namespace fields will not be very large.

Which issue(s) this PR fixes (optional, in fixes #<issue number>(, fixes #<issue_number>, ...) format, will close the issue(s) when PR gets merged):
Fixes #

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