Use new plugin SDK interface to build kubernetes_multicluster plugin

[Warashi]

What this PR does:

as title

Why we need it:

Because we introduced a new plugin SDK interface in #5698, I want to migrate the k8s multicluster plugin.
After migrating all plugins, I'll remove and refactor old SDK interfaces.

Which issue(s) this PR fixes:

Follows #5698
Part of #5530

Does this PR introduce a user-facing change?: No

• How are users affected by this change:
• Is this breaking change:
• How to migrate (if breaking change):

[codecov]

Codecov Report

Attention: Patch coverage is 0% with 8 lines in your changes missing coverage. Please review.

Project coverage is 25.65%. Comparing base (d84746b) to head (009b4b2).
Report is 1 commits behind head on master.

Files with missing lines	Patch %	Lines
...app/pipedv1/plugin/kubernetes_multicluster/main.go	0.00%	8 Missing ⚠️

Additional details and impacted files

@@           Coverage Diff           @@
##           master    #5702   +/-   ##
=======================================
  Coverage   25.64%   25.65%           
=======================================
  Files         481      481           
  Lines       51254    51259    +5     
=======================================
+ Hits        13145    13151    +6     
+ Misses      37111    37110    -1     
  Partials      998      998           

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[ffjlabo]

LGTM