feat: add support for extended release channel

[afarbos]

What type of PR is this?

/kind feature

What this PR does / why we need it:

This PR add support for the release channel extended, see:

• https://cloud.google.com/kubernetes-engine/docs/concepts/release-channels#channels
• https://pkg.go.dev/cloud.google.com/go/container/apiv1/containerpb#ReleaseChannel_EXTENDED

Which issue(s) this PR fixes (optional, in fixes #<issue number>(, fixes #<issue_number>, ...) format, will close the issue(s) when PR gets merged):
Fixes #

Special notes for your reviewer:

Please confirm that if this PR changes any image versions, then that's the sole change this PR makes.

TODOs:

• squashed commits
• includes documentation
• adds unit tests

Release note:

Add support for release channel extended

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[k8s-ci-robot]

Hi @afarbos. Thanks for your PR.

I'm waiting for a kubernetes-sigs member to verify that this patch is reasonable to test. If it is, they should reply with /ok-to-test on its own line. Until that is done, I will not automatically test new commits in this PR, but the usual testing commands by org members will still work. Regular contributors should join the org to skip this step.

Once the patch is verified, the new status will be reflected by the ok-to-test label.

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[afarbos]

make verify and make test passed

[cpanato]

/ok-to-test

[afarbos]

/retest

[afarbos]

I see OOMKilled under test in Job Pod Info info retrying in case 🤷

[afarbos]

it worked, it seems this should be all good! 🤞

[salasberryfin]

/lgtm

[damdo]

Thanks

/approve

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: afarbos, damdo

The full list of commands accepted by this bot can be found here.

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• OWNERS [damdo]

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[damdo]

It looks like the verify job is failing, let's rebase this PR on top of latest main and see if we need to regenerate the CRDs
@afarbos

[afarbos]

It looks like the verify job is failing, let's rebase this PR on top of latest main and see if we need to regenerate the CRDs @afarbos

• Rebased and added all changes generate by make generate
• ran make verify && make test both pass
• CI looks green

Let me know @damdo, I think it should be good!

[damdo]

/lgtm