🏃 Move deletePorts back to compute package

[macaptain]

Following up on @mdbooth's review of #950, this moves the deletePorts function from the networking package back to the compute package where it can be made a private function.

What this PR does / why we need it: fixes a nit from a review of #950

Special notes for your reviewer:

1. Please confirm that if this PR changes any image versions, then that's the sole change this PR makes.

TODOs:

• squashed commits

/hold

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[k8s-ci-robot]

Hi @macaptain. 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. Regular contributors should join the org to skip this step.

Once the patch is verified, the new status will be reflected by the ok-to-test label.

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[mdbooth]

/ok-to-test

[mdbooth]

/lgtm

[jichenjc]

/approve
/hold cancel

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: jichenjc, macaptain

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