Istio auth sds e2e (#12100)
Istio auth sds e2e (#12100)

* use CredentialName for SIMPLE

* cvc

* rootca

* update test.

* update test

* fix format

* update gateway config

* fix test

* fix lint

* fix test

* add comments.

* add nolint

* update cvc

* update

* update

* update

* update

* update

* update

* format

* dep ensure --update istio.io/api

* Revise per comments

* Revise

* lint

* Marshal SDS call credential config using deterministic order

* update

* update

* revise

* add comment

* update

* Update validation

* fix istio_auth_sds_e2e

* fix TestRouteSNIViaEgressGateway/*

istio/istio,smawson/istio,istio/istio,geeknoid/istio,smawson/istio,istio/istio,geeknoid/istio,istio/istio,smawson/istio,geeknoid/istio,smawson/istio,geeknoid/istio,geeknoid/istio,istio/istio,smawson/istio,smawson/istio,geeknoid/istio