fix: 테스트 코드 수정 (MIKKI-216)

Author: swjoon

backend/src/test/java/com/backend/domain/reservation/repository/ReservationRepositoryTest.java

@@ -166,7 +166,6 @@ void t03() {
 				.set("memberId", memberId)
 				.set("guestCount", i)
 				.set("reservationDate", LocalDate.of(2025, 1, 1).plusDays(i))
-				.set("guestCount", 1)
 				.set("paymentKey", "test")
 				.set("paymentMethod", "test")
 				.set("cardNumber", "121354556")

backend/src/test/java/com/backend/domain/reservationdate/repository/ReservationDateRepositoryTest.java

@@ -248,6 +248,9 @@ void t07() {
 		// When
 		reservationDateRepository.deleteOrphanReservationDate();
 
+		em.flush();
+		em.clear();
+
 		// Then
 		List<ReservationDate> findReservationDateList = reservationDateRepository.findAll();