Clean up istio gateway values

General MR

Summary

Was working through adding a Helm schema for Big Bang's Istio Gateway chart and encountered a few things that were getting passed incorrectly or as 'extra' values to the Helm chart.

The main motivation is to be able to enable "additionalProperties: false" at the root of our istio gateway values schema which would quickly alert folks if they erroneously pass in values that are incorrect or nested incorrectly.

This MR removes / moves values for Istio Gateway to match WIP schema and should not change any behavior besides correcting the default image pull config being copied over to custom gateways.

• removes .istioGatway.gateways[somegateway].monitoring (I do not think this was being used)
• moves default imagePullSecret config to target correct resources
• deletes istioGateway.gatewayCerts key from values before passing to the chart (istioGateway chart does not use)

Relevant logs/screenshots

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Linked Issue

issue

Upgrade Notices

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