[checkstyle] optimize java code checkstyle for EmptyStatement rule (#1373)

dolphinscheduler-api/src/main/java/org/apache/dolphinscheduler/api/dto/gantt/GanttDto.java

@@ -55,7 +55,7 @@ public class GanttDto {
         this();
         this.height = height;
         this.tasks = tasks;
-        this.taskNames = taskNames;;
+        this.taskNames = taskNames;
     }
     public GanttDto(int height, List<Task> tasks, List<String> taskNames, Map<String, String> taskStatus) {
         this.height = height;

style/checkstyle.xml

@@ -229,7 +229,9 @@
             <property name="illegalClasses" value="java.util.Optional, com.google.common.base.Optional"/>
         </module>
 
-        <module name="EmptyStatement"/>
+        <module name="EmptyStatement">
+            <property name="severity" value="error"/>
+        </module>
 
         <module name="JavadocStyle"/>