Epic Goal

• Add an optional capability that allows disabling the image registry operator entirely

Why is this important?

It is already possibly to run a cluster with no instantiated image registry, but the image registry operator itself always runs.  This is an unnecessary use of resources for clusters that don't need/want a registry.  Making it possible to disable this will reduce the resource footprint as well as bug risks for clusters that don't need it, such as SNO and OKE.

Acceptance Criteria

• CI - MUST be running successfully with tests automated (we have an existing CI job that runs a cluster with all optional capabilities disabled.  Passing that job will require disabling certain image registry tests when the cap is disabled)
• Release Technical Enablement - Provide necessary release enablement details and documents.
• ...

Dependencies (internal and external)

1.  MCO-499 must be completed first because we still need the CA management logic running even if the image registry operator is not running.

Previous Work (Optional):

1. The optional cap architecture and guidance for adding a new capability is described here: https://github.com/openshift/enhancements/blob/master/enhancements/installer/component-selection.md

Done Checklist

• CI - CI is running, tests are automated and merged.
• Release Enablement <link to Feature Enablement Presentation>
• DEV - Upstream code and tests merged: <link to meaningful PR or GitHub Issue>
• DEV - Upstream documentation merged: <link to meaningful PR or GitHub Issue>
• DEV - Downstream build attached to advisory: <link to errata>
• QE - Test plans in Polarion: <link or reference to Polarion>
• QE - Automated tests merged: <link or reference to automated tests>
• DOC - Downstream documentation merged: <link to meaningful PR>