Drop support for networkingv1beta1.IngressClass in kubectl

[scaliby]

What type of PR is this?

/kind cleanup

What this PR does / why we need it:

It cleans up deprecated networkingv1beta1.IngressClass so we will not have to modify ResourceDescriber logic for it when implementing kubernetes/kubectl#1769 and #133498.

Which issue(s) this PR is related to:

kubernetes/kubectl#1769

Does this PR introduce a user-facing change?

Dropped support for networking/v1beta1 IngressClass in kubectl

[k8s-ci-robot]

This issue is currently awaiting triage.

If a SIG or subproject determines this is a relevant issue, they will accept it by applying the triage/accepted label and provide further guidance.

The triage/accepted label can be added by org members by writing /triage accepted in a comment.

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 kubernetes-sigs/prow repository.

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is NOT APPROVED

This pull-request has been approved by: scaliby
Once this PR has been reviewed and has the lgtm label, please assign brianpursley for approval. For more information see the Code Review Process.

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

Needs approval from an approver in each of these files:

• staging/src/k8s.io/kubectl/OWNERS

Approvers can indicate their approval by writing /approve in a comment
Approvers can cancel approval by writing /approve cancel in a comment