fix(缺陷管理): 缺陷自定义字段处理问题

--bug=1049314 --user=宋昌昌 【缺陷管理】集成tapd-使用tapd默认模板创建缺陷-修改缺陷名称-修改后查看列表名称未修改 https://www.tapd.cn/55049933/s/1615067

backend/services/bug-management/src/main/java/io/metersphere/bug/service/BugService.java

@@ -1181,7 +1181,7 @@ public class BugService {
             for (BugCustomField bugCustomField : updateFields) {
                 BugCustomFieldExample bugCustomFieldExample = new BugCustomFieldExample();
                 bugCustomFieldExample.createCriteria().andBugIdEqualTo(bugCustomField.getBugId()).andFieldIdEqualTo(bugCustomField.getFieldId());
-                bugCustomFieldMapper.updateByExample(bugCustomField, bugCustomFieldExample);
+                bugCustomFieldMapper.updateByExampleSelective(bugCustomField, bugCustomFieldExample);
             }
             sqlSession.flushStatements();
             SqlSessionUtils.closeSqlSession(sqlSession, sqlSessionFactory);