cache cluster-registry memory based on rsr namespaces

[nishantapatil3]

Q	A
Bug fix?	no
New feature?	no
API breaks?	no
Deprecations?	no
Related tickets	fixes memory issue in multicluster scenario
License	Apache 2.0

What's in this PR?

Contains the changes required to limit namespace cache on ResourceSyncRule rules.match.namespaces This PR adds the namespaces field to chart release namespace in ResourceSyncRule.

With changes in cluster-registry-controller here https://github.com/cisco-open/cluster-registry-controller/pull/62 Limit caching on requiredNamespaces can be used in spec.rules.match.namespaces

Why?

In a large cluster with many namespaces, cluster-registry can consume memory resources and reach OOMKilled state due to memory limitations. This change adds namespaces filed to RSR rule to cache on istio-operator release namespace to reduce memory consumption.

Checklist

• [x] Implementation tested
• [x] Error handling code meets the guideline
• [x] Logging code meets the guideline
• [x] User guide and development docs updated (if needed)