fix: prevent spurious rolling updates from revision serialization differences due to 1.34 API modification

[rudeigerc]

What type of PR is this?

/kind bug

What this PR does / why we need it

When upgrading the LWS controller across client-go versions, ControllerRevision.Data.Raw can change in semantically irrelevant ways. The existing EqualRevision performs a raw-bytes comparison and treats these differences as spec changes, causing getUpdatedRevision to trigger unnecessary rolling updates.

This PR adds a semantic equivalence check as a fallback when raw-bytes comparison fails, adapting the approach from kubernetes/kubernetes#135017 for the upstream StatefulSet controller.

Which issue(s) this PR fixes

Fixes #797

Special notes for your reviewer

Does this PR introduce a user-facing change?

Prevent spurious rolling updates from revision serialization differences due to 1.34 API modification.

/cc @Edwinhr716 @ahg-g @kerthcet

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[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is NOT APPROVED

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[k8s-ci-robot]

Hi @rudeigerc. 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.

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[Edwinhr716]

/ok-to-test

[rudeigerc]

/test pull-lws-test-integration-main