Fix error of modifying kanban's panelCode

kanban-console/src/main/java/com/uas/kanban/service/impl/KanbanServiceImpl.java

@@ -14,7 +14,6 @@ import org.springframework.stereotype.Service;
 
 import java.util.Collections;
 import java.util.List;
-import java.util.Objects;
 
 /**
  * 看板
@@ -75,7 +74,7 @@ public class KanbanServiceImpl extends BaseService<Kanban> implements KanbanServ
         }
         String panelCode = jsonObject.getString("panelCode");
         String oldPanelCode = kanbanDao.findPanelCode(code);
-        if (!StringUtils.isEmpty(panelCode) && !Objects.equals(panelCode, oldPanelCode)) {
+        if (panelCode != null && !panelCode.equals(oldPanelCode)) {
             throw new OperationException("不可修改 panelCode");
         }
         panelDao.checkExist(oldPanelCode);