[PodLevelResources] Verify scheduler resource metrics account for Pod Level Resources

[toVersus]

What type of PR is this?

/kind cleanup

What this PR does / why we need it:

This is one of the PRs to enhance test coverage for KEP-2837: Pod Level Resources.

It adds a test to verify that kube_pod_resource_request and kube_pod_resource_limit metrics exposed by the kube-scheduler correctly account for Pod Level Resources. The function podRequestsAndLimitsByLifecycle(), which is used to retrieve the values of these metrics, has relied on PodRequests() and PodLimits() from k8s.io/component-helpers/resource since before KEP-2837 was implemented.

With the implementation of KEP-2837 (#128407), PodRequests() and PodLimits() now return values that take Pod Level Resources into account, so no changes were needed in the scheduler's code. While the added test cases are not exhaustive, I think they are sufficient to confirm that the metrics reflect the implementation of Pod Level Resources.

Which issue(s) this PR is related to:

KEP: kubernetes/enhancements#2837

Special notes for your reviewer:

Does this PR introduce a user-facing change?

NONE

Additional documentation e.g., KEPs (Kubernetes Enhancement Proposals), usage docs, etc.:

[KEP]: https://github.com/kubernetes/enhancements/issues/2837

[k8s-ci-robot]

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Hi @toVersus. Thanks for your PR.

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[toVersus]

/cc @ndixita

[toVersus]

/cc @sanposhiho @macsko @dom4ha
I know you’re all busy with other high-priority tasks, but if any of you have some time, I’d really appreciate it if you could review this.

[AxeZhan]

/ok-to-test

[AxeZhan]

/lgtm

[k8s-ci-robot]

LGTM label has been added.

Git tree hash: a6602008273bb170b447b631d34866ee78e3bf38

[ndixita]

/assign @kerthcet

[kerthcet]

looks good to me.
/approve

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: kerthcet, toVersus

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