[WIP] Add e2e test for multiport InferencePool enhancement

[RyanRosario]

/hold

What type of PR is this?

kind/cleanup

What this PR does / why we need it:

Adds an E2E test for multi-port enhancement. Currently verifyTrafficRouting is implemented, verifyMetrics to follow.

Which issue(s) this PR fixes:

Fixes #1768

Does this PR introduce a user-facing change?:

NONE

[linux-foundation-easycla]

The committers listed above are authorized under a signed CLA.

• ✅ login: RyanRosario / name: Ryan R. Rosario (6b1055c, 772d499, 9ba982f, ab435f8, f1e2e55)

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[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is NOT APPROVED

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

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[k8s-ci-robot]

Hi @RyanRosario. Thanks for your PR.

I'm waiting for a github.com 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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