🐛 Ensure tags and trunks for existing ports

[mquhuy]

What this PR does / why we need it:
When a port is created, it is tagged and explicitly checked if it needs a trunk, but if the port already exists for some reason, it is taken without any of those checking. This PR fixes that by adding a similar check for the existing ports, similar to the check in new ports.

Which issue(s) this PR fixes (optional, in fixes #<issue number>(, fixes #<issue_number>, ...) format, will close the issue(s) when PR gets merged):
Fixes #

Special notes for your reviewer:

Technically this rarely happens, as a failure in VM creation will clean up all ports, hence we don't normally have existing ports with same name and network ID as the one we need. Still, if that happens that there exists such a port, a problem may arise.

This is an issue with release-0.9. I'm not sure if other releases may behave in the same manner.

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

TODOs:

• squashed commits
• if necessary:
  • includes documentation
  • adds unit tests

/hold

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[k8s-ci-robot]

Hi @mquhuy. 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.

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[adilGhaffarDev]

/ok-to-test

[mquhuy]

/retest

[mquhuy]

/retest

[mquhuy]

/retest

[lentzi90]

I have rebased to make the linter happy.
This is essentially a backport of #2263