Setup for Istio Authorization Policies

General MR

Summary

Set up Istio Authorization Policies

Relevant logs/screenshots

Testing Instructions:

1. Deploy Holocron with the following values set in your overrides file:

    values:
      istio:
        enabled: true

2. Go to holocron.bigbang.dev and verify holocron comes up.
3. Delete the holocron-api-policy with the command: kubectl delete authorizationpolicy holocron-api-policy -n holocron
4. Refresh holocron.bigbang.dev, and confirm the app goes down and gives RBAC: access denied error.

Linked Issue

issue

Upgrade Notices

N/A

Relates #3 (closed)