fix(key-value-item): add overflow hidden style to item wrapper element (

#2036)

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## Self Checklist

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about the changes that needed to be released. (or didn't have to)
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## Summary
<!-- Please brief explanation of the changes made -->

fix(key-value-item): add overflow hidden style to item wrapper element

## Details
<!-- Please elaborate description of the changes -->

<img width="302" alt="스크린샷 2024-02-29 오후 2 49 11"
src="https://github.com/channel-io/bezier-react/assets/58209009/001883f3-ef32-49d9-acfe-d4f673ec0374">

scss 마이그레이션 과정에서 `overflow: hidden` 스타일이 제거되어 사용처(채널 데스크)에서 위와 같은 오버플로우
현상이 발생하는 문제를 수정합니다.

### Breaking change? (Yes/No)
<!-- If Yes, please describe the impact and migration path for users -->

No

.changeset/selfish-turkeys-boil.md

@@ -0,0 +1,5 @@
+---
+"@channel.io/bezier-react": patch
+---
+
+Add missing `overflow: hidden` style to item wrapper of `KeyValueItem` component.

packages/bezier-react/src/components/KeyValueItem/KeyValueItem.module.scss

@@ -38,6 +38,7 @@
 }
 
 .ItemWrapper {
+  overflow: hidden;
   display: flex;
   align-items: flex-start;