Add Release Candidate build support to Release Automation scripts

[aThorp96]

Overview

Add support for Release Candidate (RC) builds.

• Add a new subcommand to release manager, finalize-rc, which converts an RC build to a regular release build
• Modify the new-release command to create new versions in RC mode (with -RC-1 trailer). Subsequent new-release calls to the same version increment the RC number.
• Extend the Automated Release Actions Github Workflow to support Finalizing Release Candidate Releases.
• Add a dedicated Github Workflow for each Release Action, though each in turn simply calls the shared "Automated Release Actions" workflow with the corresponding parameters.

Schema Changes

Release files' patch-version field has been renamed release-tag

Workflow overview

When a release captain is preparing for a new release, they now do the following:

1. Create an RC build using the Github Workflow Release Action - New Release, which generates a Release File with <version>-RC-1.
2. Make any necessary changes to the versions included in the Release File
3. Run the Generate konflux configurations Github Workflow (or ensure it was run automatically), which generates the Konflux configuration files (release plan, application, etc) with version: x.y but the Release Plan's release_version set to vX.Y.Z-RC-1.
4. Ensure the various components' pull requests are all merged, Konflux resources are applied, etc. proceed as normal
5. The automatic release process will release the operator index to development (push to quay.io) and tag the image with vX.Y.Z-RC-N (e.g. v1.2.3-RC-1). The Release Captain can give this image+tag to QA.
6. When the next release candidate is needed, the Release Captain can follow the process again (minus the component-PRs) to get the next RC build (RC-2)
7. Once the release is ready for the non-RC build, the Release Captain runs the Github Workflow Release Action - Finalize RC to update the Release File with is-rc: false and drop the rc-version.
8. They then ensure the Konflux resources are all updated and applied on the cluster
9. The next release will use the release_version as normal, no -RC-n suffix.

[aThorp96]

From a call:

• track the RC version directly in the patch-version field
• rename the patch-version file to release-tag
• No dedicated create-rc-build; make new-release default to RC build