fix 'pod' in kubelet prober metrics

[a7i]

What type of PR is this?

/kind bug
/kind regression

What this PR does / why we need it:

Which issue(s) this PR fixes:

Fixes #115766

Special notes for your reviewer:

Kubernetes 1.25 Metric:

prober_probe_total{container="app-nginx",namespace="app",
pod="app-nginx",pod_uid="2de634c5-963f-4ffb-9b15-700f3f9b8bf3",
probe_type="Readiness",result="successful"
} 794

Kubernetes 1.24 Metric:

prober_probe_total{container="app-nginx",namespace="app",
pod="app-nginx-799b74869b-mmhr7",pod_uid="4550420b-6a0c-4d59-a486-f5b3a69ebdf8",
probe_type="Readiness",result="successful"
} 81023

This breaking change causes the metrics to not get processed by datadog core which relies on actual pod name.

Does this PR introduce a user-facing change?

Yes, but it reverts to initial functionality.

Fixes a 1.25 regression to revert kubelet prober metrics `pod` tag to include actual pod name

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

/cc @jackfrancis @SergeyKanzhelev from discussion here

[k8s-ci-robot]

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/ok-to-test

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[bart0sh]

/triage accepted
/priority important-soon
/ok-to-test

[a7i]

/retest-required

[mindw]

Please consider back porting this fix to supported releases - 1.25+. Thanks!

[dosmanak]

Hi, thank you for making this simple revert. I wonder why the issue has not been yet targeted by the core team as it seems clear.
I hope in soon merge in the main and possible backport in current release.

[derekwaynecarr]

I think we should take the revert and return to prior behavior given the regression.

Would like @SergeyKanzhelev to chime in as well since he reviewed prior PR.

/lgtm

[k8s-ci-robot]

LGTM label has been added.

Git tree hash: e3edc4be51d2d79b817e50e33f20882a4cc59f75

[derekwaynecarr]

pending review from a few others.

/hold

[dims]

/milestone v1.28

[dims]

/milestone v1.28

[SergeyKanzhelev]

/lgtm

The concern was the cardinality explosion as pod name has replica's random part. However we are not making things worse exponentially - we already had a metric for success.

I think the right long term fix will be having this logic as a default, but also allow to override the app name in those metrics based on some attributes

[dims]

/approve
/lgtm

per discussion on slack and here, we need to get this in.

[dims]

/hold cancel

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: a7i, dims, SergeyKanzhelev

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