feat: add pod acknowledged time metric

[njtran]

Fixes #N/A

Description
This emits a metric when we consider a pod for scheduling. This will give an accurate representation of when Karpenter actually first considers the pod for scheduling. Currently this would emit for every pod for every scheduling loop, so if a pod fails to schedule, it would be considered again.

How was this change tested?
havent yet

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[k8s-ci-robot]

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[coveralls]

Pull Request Test Coverage Report for Build 11748399818

Warning: This coverage report may be inaccurate.

This pull request's base commit is no longer the HEAD commit of its target branch. This means it includes changes from outside the original pull request, including, potentially, unrelated coverage changes.

• For more information on this, see Tracking coverage changes with pull request builds.
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• For a quick fix, rebase this PR at GitHub. Your next report should be accurate.

Details

• 18 of 18 (100.0%) changed or added relevant lines in 3 files are covered.
• 4 unchanged lines in 1 file lost coverage.
• Overall coverage increased (+0.03%) to 80.956%

---

Files with Coverage Reduction	New Missed Lines	%
pkg/controllers/disruption/consolidation.go	4	87.25%

Totals
Change from base Build 11747362633:	0.03%
Covered Lines:	8532
Relevant Lines:	10539

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💛 - Coveralls

[k8s-ci-robot]

PR needs rebase.

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