fix(form-label/helper-text): fix merging of classname not working pro…

…perly when inside a `FormControl` (#2156)

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- [x] I wrote a PR title in **English** and added an appropriate
**label** to the PR.
- [x] I wrote the commit message in **English** and to follow [**the
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- [x] I [added the
**changeset**](https://github.com/changesets/changesets/blob/main/docs/adding-a-changeset.md)
about the changes that needed to be released. (or didn't have to)
- [x] I wrote or updated **documentation** related to the changes. (or
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  - Windows: Chrome, Edge, (Optional) Firefox
  - macOS: Chrome, Edge, Safari, (Optional) Firefox

## Summary

<!-- Please brief explanation of the changes made -->

FormControl 내부에 위치한 FormLabel, FormHelperText(ErrorMessage)에 className
오버라이드가 잘 적용되지 않는 문제를 수정합니다.

## Details

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

베지어 마이그레이션 과정에서 FormControl이 FormLabel, FormHelperText에게 래퍼 스타일을 전달하는
과정이 변경되었습니다.

변경 과정에서 `get***Props` 함수가 반환하는 `className` 과 인자로 받는 `className` 의 속성명이
서로 겹치게 되었는데, 이 때 두 className이 모두 적용되는 게 아니라 인자로 받는 `className` 이 우선순위를
가지고 적용되면서 FormControl이 전달하는 래퍼 스타일이 무시되는 버그가 있었습니다. 이를 수정합니다.

### Breaking change? (Yes/No)

No

<!-- If Yes, please describe the impact and migration path for users -->

## References

<!-- Please list any other resources or points the reviewer should be
aware of -->

- [Channel
Desk](https://desk.channel.io/root/threads/groups/Bug-10/6617adea666db15cf58f/6617adea666db15cf58f)

.changeset/witty-icons-beg.md

@@ -0,0 +1,5 @@
+---
+"@channel.io/bezier-react": patch
+---
+
+Fixes an issue where injecting `className` into `FormLabel`, `FormHelperText` inside a `FormControl` does not apply styles correctly.

packages/bezier-react/src/components/FormHelperText/FormHelperText.tsx

@@ -22,7 +22,7 @@ export const FORM_ERROR_MESSAGE_TEST_ID = 'bezier-form-error-message'
 
 const BaseHelperText = forwardRef<HTMLSpanElement, BaseHelperTextProps>(
   function BaseHelperText(props, forwardedRef) {
-    const { type, typo = '13', children, ...rest } = props
+    const { type, typo = '13', children, className, ...rest } = props
 
     const contextValue = useFormControlContext()
     const getProps =
@@ -52,7 +52,11 @@ const BaseHelperText = forwardRef<HTMLSpanElement, BaseHelperTextProps>(
       <Text
         ref={mergedRef}
         as="p"
-        className={classNames(styles.FormHelperText, formControlClassName)}
+        className={classNames(
+          styles.FormHelperText,
+          formControlClassName,
+          className
+        )}
         typo={typo}
         align="left"
         {...ownProps}

packages/bezier-react/src/components/FormLabel/FormLabel.tsx

@@ -35,6 +35,7 @@ export const FormLabel = forwardRef<HTMLLabelElement, FormLabelProps>(
       help,
       bold = true,
       color = 'txt-black-darkest',
+      className,
       children,
       ...rest
     } = props
@@ -67,7 +68,8 @@ export const FormLabel = forwardRef<HTMLLabelElement, FormLabelProps>(
       <Text
         className={classNames(
           styles.LabelText,
-          !HelpComponent && formControlClassName
+          !HelpComponent && formControlClassName,
+          className
         )}
         ref={forwardedRef}
         as="label"
@@ -91,7 +93,7 @@ export const FormLabel = forwardRef<HTMLLabelElement, FormLabelProps>(
       <LegacyHStack
         align="center"
         spacing={6}
-        className={HelpComponent && formControlClassName}
+        className={formControlClassName}
       >
         <LegacyStackItem
           shrink