deprecate kubelet certificate management mode

[qclc]

What type of PR is this?

Uncomment only one /kind <> line, hit enter to put that in a new line, and remove leading whitespace from that line:
/kind bug
/kind documentation
/kind enhancement
/kind good-first-issue
/kind feature
/kind question
/kind design
/sig ai
/sig iot
/sig network
/sig storage
/sig storage
/kind design

What this PR does / why we need it:

1. Deprecate kubelet certificate management mode (Yurthub shares certificates with Kubelet)
2. Delete the relevant code for sharing the certificate with kubelet

Which issue(s) this PR fixes:

Fixes #573

Special notes for your reviewer:

@rambohe-ch please take review

Does this PR introduce a user-facing change?

After this code is merged, if the --cert-mgr-mode flag of yurthub is set to kubelet , yurthub will report an error message: validate options: cert manage mode kubelet is not supported, and exit.

other Note

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In response to this:

What type of PR is this?

Uncomment only one /kind <> line, hit enter to put that in a new line, and remove leading whitespace from that line:
/kind bug
/kind documentation
/kind enhancement
/kind good-first-issue
/kind feature
/kind question
/kind design
/sig ai
/sig iot
/sig network
/sig storage
/sig storage
/kind design

What this PR does / why we need it:

1. Deprecate kubelet certificate management mode (Yurthub shares certificates with Kubelet)
2. Delete the relevant code for sharing the certificate with kubelet

Which issue(s) this PR fixes:

Fixes #573

Special notes for your reviewer:

@rambohe-ch please take review

Does this PR introduce a user-facing change?

After this code is merged, if the --cert-mgr-mode flag of yurthub is set to kubelet , yurthub will report an error message: validate options: cert manage mode kubelet is not supported, and exit.

other Note

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[rambohe-ch]

/lgtm
/approve

[openyurt-bot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: qclc, rambohe-ch

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• OWNERS [rambohe-ch]

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