[Style] SectionTitle 컴포넌트 스타일 수정 (#281)

* fix: optional desc 적용

* fix: 설명 있을때만 돔 생성

* fix: 윤호님 리뷰 적용

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Co-authored-by: byun sumi <sumi@adenasoft.com>

src/components/SectionTitle/SectionTitle.tsx

@@ -17,9 +17,9 @@ interface SectionTitleProps {
 export function SectionTitle({ label, title, description, ...layoutProps }: SectionTitleProps) {
   return (
     <div css={layoutCss} {...layoutProps}>
-      <h4 css={labelCss}>{label}</h4>
-      <h2 css={titleCss}>{title}</h2>
-      <p css={descriptionCss}>{description}</p>
+      {label && <h4 css={labelCss}>{label}</h4>}
+      {title && <h2 css={titleCss}>{title}</h2>}
+      {description && <p css={descriptionCss}>{description}</p>}
     </div>
   );
 }