enhance(frontend): adminのファイルリストでセンシティブファイルに枠線を追加

[kakkokari-gtyih]

What

Why

Fix #14389

Additional info (optional)

Checklist

• [x] Read the contribution guide
• [ ] Test working in a local environment
• [ ] (If needed) Add story of storybook
• [x] (If needed) Update CHANGELOG.md
• [ ] (If possible) Add tests

[codecov[bot]]

Codecov Report

Attention: Patch coverage is 95.23810% with 1 line in your changes missing coverage. Please review.

Project coverage is 19.99%. Comparing base (f7398fa) to head (11cc4a8). Report is 17 commits behind head on develop.

Files with missing lines	Patch %	Lines
...ges/frontend/src/components/MkFileListForAdmin.vue	0.00%	1 Missing :warning:

Additional details and impacted files

```diff @@ Coverage Diff @@ ## develop #14510 +/- ## =========================================== + Coverage 19.97% 19.99% +0.01% =========================================== Files 725 725 Lines 100569 100588 +19 Branches 1047 1047 =========================================== + Hits 20089 20108 +19 Misses 79936 79936 Partials 544 544 ```

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[kakkokari-gtyih]

コンフリクト解消

[syuilo]

🙏🏿