Implement LoadManifests with Kustomize template

[Warashi]

What this PR does:

as title

Why we need it:

We must support the kustomize templating method in the k8s plugin because the pipedv0 supports it.

Which issue(s) this PR fixes:

Part of #4980

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 65.85366% with 14 lines in your changes missing coverage. Please review.

Project coverage is 24.41%. Comparing base (c265522) to head (07ad220).
Report is 1 commits behind head on master.

Files with missing lines	Patch %	Lines
...g/app/pipedv1/plugin/kubernetes/provider/loader.go	0.00%	11 Missing ⚠️
...pp/pipedv1/plugin/kubernetes/provider/kustomize.go	90.00%	2 Missing and 1 partial ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #5291      +/-   ##
==========================================
+ Coverage   24.37%   24.41%   +0.03%     
==========================================
  Files         442      443       +1     
  Lines       46902    46941      +39     
==========================================
+ Hits        11432    11459      +27     
- Misses      34560    34571      +11     
- Partials      910      911       +1     

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[ffjlabo]

LGTM

[khanhtc1202]

Here you go 👍