Promote RetryGenerateName to beta

[jpbetz]

What type of PR is this?

/kind feature

What this PR does / why we need it:

Special notes for your reviewer:

Does this PR introduce a user-facing change?

Promoted `generateName` retries to beta, and made the `NameGenerationRetries` feature gate
enabled by default.
You can read https://kep.k8s.io/4420 for more details.

Additional documentation e.g., KEPs (Kubernetes Enhancement Proposals), usage docs, etc.:

• KEP-4420

/sig api-machinery
/milestone v1.31

[jpbetz]

/assign @deads2k
This is just a feature gate flip.

[cici37]

/triage accepted

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: jpbetz

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• pkg/features/OWNERS [jpbetz]
• staging/src/k8s.io/apiserver/OWNERS [jpbetz]

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[deads2k]

matches expectations

/lgtm

[k8s-ci-robot]

LGTM label has been added.

Git tree hash: cd1c3efa859ac2d0a6abb44d7cea67fcfb1290ed

[sftim]

Changelog suggestion

-GenerateName retry is now in beta and enabled by default. Check out https://github.com/kubernetes/enhancements/issues/4420 for more details.
+Promoted `generateName` retries to beta, and made the `NameGenerationRetries` feature gate
+enabled by default.
+You can read https://kep.k8s.io/4420 for more details.

[sftim]

When we document this change, let's update https://kubernetes.io/docs/reference/using-api/api-concepts/#generated-values with a brief mention of retries.

[jpbetz]

When we document this change, let's update https://kubernetes.io/docs/reference/using-api/api-concepts/#generated-values with a brief mention of retries.

Will do. Thanks Tim for you helping get this one done early in the cycle!