[apiserver-kubelet/tracing]: add distributed tracing config variables

[ugur99]

What type of PR is this?
/kind feature

What this PR does / why we need it:
This MR contains some enhancements that make possible to enable distributed tracing for kubelet and kube-apiserver components.

Which issue(s) this PR fixes:

Fixes # none

Special notes for your reviewer:
APIServerTracing and KubeletTracing have been graduated to beta version with v1.27.

Refs:

• Feature Gates
• Traces For Kubernetes System Components

Does this PR introduce a user-facing change?:

[kube-apiserver] added distributed tracing config variables for kube-apiserver (`kube_apiserver_tracing`,`kube_apiserver_tracing_endpoint`,`kube_apiserver_tracing_sampling_rate_per_million`); it is disabled by default.
[kubelet] added distributed tracing config variables for kubelet (`kubelet_tracing`,`kubelet_tracing_endpoint`,`kubelet_tracing_sampling_rate_per_million`); it is disabled by default.

[k8s-ci-robot]

Hi @ugur99. Thanks for your PR.

I'm waiting for a kubernetes-sigs 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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[yankay]

/ok-to-test

[VannTen]

As we're dropping 1.26 support from master, no need to support it.

Also I think you're release should separate kubelet and kube_apiserver tracing entry
If I understand the doc correctly, the two features are independent from each other.

[ugur99]

Hi @VannTen thank you for the looking at this.

Ah sure; I fixed it.

As we're dropping 1.26 support from master, no need to support it.

Yes, there is no dependency between them.

If I understand the doc correctly, the two features are independent from each other.

Sure, how can I do that? Would splitting the release notes into two lines work?

Also I think you're release should separate kubelet and kube_apiserver tracing entry

[VannTen]

Yeah two lines are fine !
/lgtm
/assign @mzaian

[mzaian]

Thanks a lot @ugur99

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: mzaian, ugur99

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