Feature: support argo rollouts extension in idpbuilder

[squidboylan]

Have you searched for this feature request?

• I searched but did not find similar requests

Problem Statement

We can easily install argo-rollouts via the stacks/package feature, but we don't have a good way to install the argo-rollouts extension that adds argo-rollouts features to the argocd UI.

Possible Solution

The easiest solution is to install the rollout extension in every cluster using the instructions in https://github.com/argoproj-labs/rollout-extension but I'm not sure if that's an acceptable solution.

Alternatives Considered

We don't have a great way to customize our argocd install at cluster creation time from what I'm seeing due to our kustomize build of the manifests at compile time. Not sure if we want a way to render templates for our argocd install at cluster creation time, it seems like a significant maintenance add but might be necessary for some features.

[jaypz]

What I've been doing to get this to work locally is after a successful idpbuilder create I run

	kubectl -n argocd patch --patch-file  argo-server-rollout-extension-patch.yaml deployment/argocd-server

Either from a Makefile or manually, where the yaml file is the patch listed from the docs; re-running idpbuilder create does not appear to undo this patch

Something more official could be nice though