Fix import groups in kubernetes/planpreview/plugin.go

[Warashi]

What this PR does:

SSIA

Why we need it:

The CI is failing on master branch. ref; https://github.com/pipe-cd/pipecd/actions/runs/17705684314/job/50317496182#step:3:119

Which issue(s) this PR fixes:

Fixes #

Does this PR introduce a user-facing change?:

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

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 28.70%. Comparing base (2cd6855) to head (57ff9c4).
⚠️ Report is 1 commits behind head on master.

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #6225      +/-   ##
==========================================
+ Coverage   28.69%   28.70%   +0.01%     
==========================================
  Files         560      560              
  Lines       59728    59728              
==========================================
+ Hits        17138    17144       +6     
+ Misses      41274    41268       -6     
  Partials     1316     1316              

Flag	Coverage Δ
.	23.23% <ø> (+0.01%)	⬆️
.-pkg-app-pipedv1-plugin-analysis	32.64% <ø> (ø)
.-pkg-app-pipedv1-plugin-kubernetes	57.90% <ø> (ø)
.-pkg-app-pipedv1-plugin-kubernetes_multicluster	67.48% <ø> (ø)
.-pkg-app-pipedv1-plugin-scriptrun	54.83% <ø> (ø)
.-pkg-app-pipedv1-plugin-terraform	39.49% <ø> (ø)
.-pkg-app-pipedv1-plugin-wait	35.51% <ø> (ø)
.-pkg-app-pipedv1-plugin-waitapproval	55.73% <ø> (ø)
.-pkg-plugin-sdk	50.47% <ø> (ø)
.-tool-actions-gh-release	19.23% <ø> (ø)
.-tool-actions-plan-preview	25.51% <ø> (ø)
.-tool-codegen-protoc-gen-auth	0.00% <ø> (ø)

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[khanhtc1202]

Nice catch, thank you 🙌

[ffjlabo]

Thank you so much!