fix:获取分部学年制的年级列表报错

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

@@ -92,6 +92,7 @@ public class OrganizationServiceImpl extends BaseServiceImpl<Integer, Organizati
 		Map<Integer, String> gradeMap = new HashMap<>();
 
 		if(Objects.isNull(organization)){
+			gradeMap.put(GradeTypeEnum.SIX_PLUS.getCode(), GradeTypeEnum.SIX_PLUS.getDesc());
 			return gradeMap;
 		}