KEP-2170: Implement validations for TrainingRuntime and ClusterTrainingRuntime

[tenzen-y]

Related: #2170

We should create validations for the TrainingRuntime and ClusterTrainingRuntime, using the following tools:

• Mutating Webhooks
• CEL validations
• controller-tools/kubebuilder annotations

/area webhook

[tenzen-y]

/area webhook

[andreyvelich]

/assign @akshaychitneni

[google-oss-prow]

@andreyvelich: GitHub didn't allow me to assign the following users: akshaychitneni.

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In response to this:

/assign @akshaychitneni

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[tenzen-y]

@akshaychitneni Could you say /assign?

[akshaychitneni]

/assign

[github-actions]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[akshaychitneni]

/assign

[akshaychitneni]

/remove-lifecycle stale

[andreyvelich]

This was fixed by: #2313

[tenzen-y]

This was fixed by: #2313

This is still under development here: #2307

/reopen

[google-oss-prow]

@tenzen-y: Reopened this issue.

In response to this:

This was fixed by: #2313

This is still under development here: #2307

/reopen

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/test-infra repository.