Add validation options for static pod

[yuanwang04]

What type of PR is this?

/kind bug

What this PR does / why we need it:

Fixes #135030 allowing validation options for static pods. The empty validation options disallowed restart rules, and other features for static pods.

Which issue(s) this PR is related to:

Fixes #135030
kubernetes/enhancements#5307

Special notes for your reviewer:

Does this PR introduce a user-facing change?

Fixes an issue that disallowed restart policies and restart rules on static pods.

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

KEP: https://github.com/kubernetes/enhancements/issues/5307

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[yuanwang04]

/cc @SergeyKanzhelev

[k8s-ci-robot]

@yuanwang04: The following test failed, say /retest to rerun all failed tests or /retest-required to rerun all mandatory failed tests:

Test name	Commit	Details	Required	Rerun command
pull-kubernetes-unit-windows-master	308a53d	link	false	/test pull-kubernetes-unit-windows-master

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[HirazawaUi]

For static pods, PodValidationOptions will take effect when creating the mirror pod.

If we previously passed an empty PodValidationOptions, it means that all its options were false (the zero value for bool types). This also implies that creating a static pod would bypass all relevant API field validations until it creates the mirror pod. Will this affect the restart rules functionality?

This seems like a reasonable bug fix, but I'm concerned that this fix might break some existing user behaviors. It affects not only the validation of restart rules but also the validation of other feature gate-related API fields.

If the kubelet runs in standalone mode, then these pods will not undergo validation for these feature gate-related API fields. I'm not sure if any users rely on this use case...