fix

examcloud-core-questions-service/src/main/java/cn/com/qmth/examcloud/core/questions/service/PaperStructService.java

@@ -526,7 +526,7 @@ public class PaperStructService {
         // 从数据库中获取
         Query query = new Query();
         query.addCriteria(Criteria.where("_id").is(new ObjectId(paperStructId)));
-        ps = this.mongoTemplate.findOne(query, PaperStructCache.class);
+        ps = this.mongoTemplate.findOne(query,PaperStructCache.class,"paperStruct");
         if (ps == null) {
             throw new StatusException("未找到试卷结构:" + paperStructId);
         }