fix: (#740) .map을 사용하며 key를 설정하지 않아 발생한 오류 해결

frontend/src/pages/ReportAlarmPage/ReportApproveResult/index.tsx

@@ -34,7 +34,7 @@ export default function ReportApproveResult() {
  <b>사유 </b>
  <S.List>
  {[...new Set(data.reasonList.map(each => REPORT_MESSAGE[each]))].map(reason => {
- return <S.ListItem>{reason}</S.ListItem>;
+ return <S.ListItem key={reason}>{reason}</S.ListItem>;
  })}
  </S.List>
  </S.ListItem>