fix(frontend): 絵文字関連のスタイルが崩れていたのを修正

[sleep-moe]

What

MkReactionsViewer.details.vue

MkReactionTooltip.vue

MkNotification.vue

MkEmojiPicker.vue

custom-emojis-manager.vue

Why

Additional info (optional)

Checklist

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

[sonarcloud[bot]]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarCloud