🐛 Fix: palette 필드 삭제로 인한 쿼리문 수정

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- 관련: #429

storage/db-mysql-v2/src/main/java/com/namo/spring/db/mysql/domains/schedule/repository/ParticipantRepository.java

@@ -39,7 +39,7 @@ public interface ParticipantRepository extends JpaRepository<Participant, Long>
 
     boolean existsByScheduleIdAndAnonymousId(Long scheduleId, Long anonymousId);
 
-    @Query("SELECT p FROM Participant p JOIN FETCH p.schedule s LEFT JOIN FETCH p.palette " +
+    @Query("SELECT p FROM Participant p JOIN FETCH p.schedule s " +
         "WHERE s.id = :scheduleId AND s.scheduleType = :scheduleType ")
     List<Participant> findParticipantsByScheduleIdAndStatusAndType(Long scheduleId, int scheduleType);