feat: add kube_pod_container_status_last_terminated_timestamp metric

[tetianakravchenko]

What this PR does / why we need it:
Adds kube_pod_container_status_last_terminated_timestamp metric to report the time when container was last time terminated with the kube_pod_container_status_last_terminated_reason. This metric is useful for cases like getting the crash situation - as described in this issue: #1805 (comment)

How does this change affect the cardinality of KSM: (increases, decreases or does not change cardinality)
Adds a new metric in cases when the kube_pod_container_status_last_terminated_reason is reported

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 #

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[dashpole]

/triage accepted
/assign @rexagod

[rexagod]

@tetianakravchenko Tests seem to be failing here.

[tetianakravchenko]

@tetianakravchenko Tests seem to be failing here.

Hey @rexagod I've fixed tests, please have a look

[tetianakravchenko]

Hey @rexagod @mrueg could you please check this PR?

[rexagod]

This looks good, just a nit. :)

[rexagod]

Suggested change

	"Last terminated time for a pod container, when container was terminated with kube_pod_container_status_last_terminated_reason, in unix timestamp.",
	"Last terminated time for a pod container in unix timestamp.",

Is when container was terminated with kube_pod_container_status_last_terminated_reason necessary here?

[tetianakravchenko]

Hey @rexagod , thank you for the feedback! I've tried to be more precise in the description, but I think you are right, there is no need to keep it.
Cleaned it up in this commit - 393430e, please have a look

[StephanErb]

This feature would be super helpful! Anything missing to get this in? :)

[tetianakravchenko]

Hey @rexagod could you please have another look on this PR?

[mrueg]

/lgtm

Thanks for your contribution!

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: mrueg, tetianakravchenko

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