deep copy slice object during append

[kmala]

Since p is slice, its value is changed during the tree traversal(iterate). Hence use deep copy instead.

fixes https://github.com/kubernetes/kubernetes/issues/119141

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[torredil]

/ok-to-test

[dims]

/assign @liggitt

[kmala]

A few comments for simplifying the test @apelisse i had simplified the test, can you please review it again.

[Tusenka]

Could you explain why this PR will fix the issue. What is the cause of the issue?

[kmala]

Could you explain why this PR will fix the issue. What is the cause of the issue?

This will fix the issue because on apply this function gets called and it returns the wrong result. The cause as i mentioned in the description is because of doing shallow copy slice during iterate.

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: apelisse, kmala

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