WIP: go 1.25.2 related fixes / tests

[BenTheElder]

What type of PR is this?

/kind bug

What this PR does / why we need it:

Various small fixes related to go 1.25.2 changes.
TODO: regression integration test for cert changes.

We will wait for go 1.25.3 to upgrade go.

#134487 (comment)

Which issue(s) this PR is related to:

Special notes for your reviewer:

Does this PR introduce a user-facing change?

NONE

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

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[dims]

/approve

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is NOT APPROVED

This pull-request has been approved by: BenTheElder, dims
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