OCP 4.20 Updates for ACM and ODF

[kenmoini]

A couple of version bumps for ACM/ODF/COO/OL/Loki for OpenShift 4.20

[gferreir]

I noticed that part of the work has already landed in main through separate commits — wanted to flag this to help clarify the current state and what still needs to happen.

Changes already in main (committed separately)

Three sets of files from this PR were committed directly to the main branch while the PR was open:

• ACM release-2.15 overlay — committed by @giofontana on Feb 6 (c3a8355)
• ODF stable-4.20 overlay — committed by @giofontana on Feb 13 (4c57177)
• COO overlays/stable/ — committed by @strangiato on Apr 25 (879cacb)

The PR will need a rebase to remove these files from the diff before it can be merged cleanly.

Incomplete COO state in main — the key remaining gap

The COO stable overlay exists in main (via 879cacb), but the base subscription.yaml was not updated alongside it. This means the overlay currently installs COO into openshift-operators — the old namespace — rather than the dedicated one this PR intends:

# main: cluster-observability-operator/operator/base/subscription.yaml
metadata:
  namespace: openshift-operators   # still the old namespace

# PR #408: cluster-observability-operator/operator/base/subscription.yaml
metadata:
  namespace: openshift-cluster-observability-operator   # dedicated namespace

The stable overlay landed in main without the namespace restructuring (new Namespace resource, new OperatorGroup, updated base/subscription.yaml, and the development overlay refactor) that gives it its intended meaning. The overlay is half-merged: the shell is there, but the behavior change is not.

What still needs to land

The remaining unreleased changes from this PR are:

• COO namespace restructuring (base/subscription.yaml, base/namespace.yaml, base/operatorgroup.yaml, overlays/development/ refactor)
• Loki stable-6.3 and stable-6.4 overlays
• OpenShift Logging stable-6.3 and stable-6.4 overlays

A few observations on the COO restructuring specifically:

The # namespace: openshift-operators comment in base/subscription.yaml should be removed rather than left commented out. The development overlay's kustomization.yaml has a commented-out patches block that is dead code after the switch to a standalone subscription. The stable overlay (already in main) has no README.md, while development does — a one-liner describing the dedicated namespace target would be consistent. Finally, users migrating from development to stable will land in different namespaces and need to manually uninstall from openshift-operators first — worth documenting in the development/README.md.

Suggested next steps

1. Rebase the branch against current main to drop the ACM, ODF, and COO stable overlay files already committed.
2. Confirm with maintainers whether the COO namespace restructuring is still the desired path (given that stable already landed in main targeting openshift-operators). If yes, proceed with the base changes. If not, the remaining COO changes in this PR would need to be revised.
3. The Loki and Logging overlays look correct and ready to merge once the rebase is done.