MCO-2120: Rework OS Image Stream label classification

[pablintino]

- What I did

Replace the single ostree.linux discriminator with configurable label matchers that explicitly classify OS images ostree.bootable, containers.bootc) and extensions images (io.openshift.os.extensions).
Images that match no discriminator now return nil instead of defaulting to extensions.

- How to verify it

Regular CI tests are enough to verify this change.

- Description for the changelog

OS image streams now use explicit label matchers (ostree.bootable, containers.bootc, io.openshift.os.extensions) instead of a single ostree.linux discriminator to classify OS and extensions images

[openshift-ci-robot]

@pablintino: This pull request references MCO-2120 which is a valid jira issue.

Warning: The referenced jira issue has an invalid target version for the target branch this PR targets: expected the story to target the "4.22.0" version, but no target version was set.

Details

In response to this:

- What I did

Replace the single ostree.linux discriminator with configurable label matchers that explicitly classify OS images ostree.bootable, containers.bootc) and extensions images (io.openshift.os.extensions).
Images that match no discriminator now return nil instead of defaulting to extensions.

- How to verify it

Regular CI tests are enough to verify this change.

- Description for the changelog

OS image streams now use explicit label matchers (ostree.bootable, containers.bootc, io.openshift.os.extensions) instead of a single ostree.linux discriminator to classify OS and extensions images

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the openshift-eng/jira-lifecycle-plugin repository.

[openshift-ci]

Skipping CI for Draft Pull Request.
If you want CI signal for your change, please convert it to an actual PR.
You can still manually trigger a test run with /test all

[dustymabe]

seems reasonable

/approve

I assume someone else from MCO should review?

[openshift-ci]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: dustymabe, pablintino

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Details

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• OWNERS [pablintino]

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