[Java] Remove java api sub package from test module (#8853)

streaming/java/streaming-api/src/main/java/io/ray/streaming/message/Record.java

@@ -3,7 +3,6 @@ package io.ray.streaming.message;
 import java.io.Serializable;
 import java.util.Objects;
 
-
 public class Record<T> implements Serializable {
   protected transient String stream;
   protected T value;

streaming/java/streaming-api/src/main/java/io/ray/streaming/operator/OneInputOperator.java

@@ -2,7 +2,6 @@ package io.ray.streaming.operator;
 
 import io.ray.streaming.message.Record;
 
-
 public interface OneInputOperator<T> extends Operator {
 
   void processElement(Record<T> record) throws Exception;

streaming/java/streaming-api/src/main/java/io/ray/streaming/operator/TwoInputOperator.java

@@ -2,7 +2,6 @@ package io.ray.streaming.operator;
 
 import io.ray.streaming.message.Record;
 
-
 public interface TwoInputOperator<T, O> extends Operator {
 
   void processElement(Record<T> record1, Record<O> record2);

streaming/java/streaming-api/src/main/java/io/ray/streaming/operator/impl/MapOperator.java

@@ -5,7 +5,6 @@ import io.ray.streaming.message.Record;
 import io.ray.streaming.operator.OneInputOperator;
 import io.ray.streaming.operator.StreamOperator;
 
-
 public class MapOperator<T, R> extends StreamOperator<MapFunction<T, R>> implements
     OneInputOperator<T> {
 

streaming/java/streaming-api/src/main/java/io/ray/streaming/operator/impl/SinkOperator.java

@@ -5,7 +5,6 @@ import io.ray.streaming.message.Record;
 import io.ray.streaming.operator.OneInputOperator;
 import io.ray.streaming.operator.StreamOperator;
 
-
 public class SinkOperator<T> extends StreamOperator<SinkFunction<T>> implements
     OneInputOperator<T> {