When upgrading istio-gateway, authpol lookup causes authpol deletion

Motivation

The ingressgateway authorization policy can be deleted when upgrading multiple gateways at the same time. Since the charts do a lookup during templating and only create the authpol in the event it's not found, upgrading multiple gateways at the same time can result in them all deciding not to create the authpol.

Acceptance Criteria

• The authpol (and other lookup-based resources) must be updated to not conflict with each other