fix: 批量调整排除请假学员

mec-biz/src/main/java/com/ym/mec/biz/service/impl/CourseScheduleServiceImpl.java

@@ -1456,7 +1456,7 @@ public class CourseScheduleServiceImpl extends BaseServiceImpl<Long, CourseSched
 				return false;
 			}
 			if(!courseLeaveStudentIdsMap.containsKey(sa.getCourseScheduleId())){
-				courseLeaveStudentIdsMap.put(sa.getCourseScheduleId(), Collections.EMPTY_SET);
+				courseLeaveStudentIdsMap.put(sa.getCourseScheduleId(), new HashSet<>());
 			}
 			CourseSchedule cs = idCourseMap.get(sa.getCourseScheduleId());
 			if(DateUtil.addHours(sa.getCreateTime(),4).compareTo(cs.getStartClassTime())<0){