Add tests for ObjectDiff, ObjectGoPrintDiff and ObjectGoPrintSideBySide

[magic-peach]

What type of PR is this?
/kind test

What this PR does / why we need it:

ObjectDiff, ObjectGoPrintDiff, and ObjectGoPrintSideBySide had zero test coverage, leaving the diff package at 0% before this change.

Which issue(s) this PR fixes:
Fixes #

Special notes for your reviewer:

Verified with go test ./diff/...: all 9 tests pass. Package coverage goes from 0% to 88.1%.

Release note:

NONE

[kubernetes-prow]

@magic-peach: The label(s) kind/test cannot be applied, because the repository doesn't have them.

Details

In response to this:

What type of PR is this?
/kind test

What this PR does / why we need it:

ObjectDiff, ObjectGoPrintDiff, and ObjectGoPrintSideBySide had zero test coverage, leaving the diff package at 0% before this change.

Which issue(s) this PR fixes:
Fixes #

Special notes for your reviewer:

Verified with go test ./diff/...: all 9 tests pass. Package coverage goes from 0% to 88.1%.

Release note:

NONE

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.

[kubernetes-prow]

[APPROVALNOTIFIER] This PR is NOT APPROVED

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

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

Details

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• OWNERS

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[skitt]

See https://kubernetes.slack.com/archives/C01672LSZL0/p1789992857325439

/close

[kubernetes-prow]

@skitt: Closed this PR.

Details

In response to this:

See https://kubernetes.slack.com/archives/C01672LSZL0/p1789992857325439

/close

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.