[EC-95] refactor: 캘린더 컴포넌트 파일명 변경 (#75)

- calendar 에서 Calendar로 변경
- 파일명 변경에 따른 StudentAttendance 페이지 내의 Calendar import 경로
  변경

Author: DaeJungYoon

client/src/components/calendar/calendar.jsx

@@ -21,7 +21,6 @@ export default function Calendar({ attendanceData }) {
       const holidayList = await fetchHolidays(year, month);
       setHolidays(holidayList);
     };
-
     getHolidays();
   }, [currentDate]);
 

client/src/pages/studentAttendance/StudentAttendance.jsx

@@ -3,7 +3,7 @@ import styles from "./StudentAttendance.module.css"
 import DashBoardItem from '../../components/dashBoardItem/DashBoardItem';
 import DataBoard from '../../components/dataBoard/DataBoard';
 import ProgressBar from '../../components/progressBar/ProgressBar';
-import Calendar from '../../components/calendar/calendar';
+import Calendar from '../../components/calendar/Calendar';
 export default function StudentAttendance() {
   const attendanceRatio = 56;
   const lateCount = 3;