GH-3592: Scatter-Gather: applySeq=true by default

Fixes https://github.com/spring-projects/spring-integration/issues/3592

* Configure XML parser & Java DSL for Scatter-Gather, based on the
`RecipientListRouter` to set an `applySequence` to `true` by default.
This will make a `gatherer` part to fully rely on the default correlation
strategies

spring-integration-jmx/src/test/java/org/springframework/integration/monitor/ScatterGatherHandlerIntegrationTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2014-2019 the original author or authors.
+ * Copyright 2014-2022 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -22,8 +22,7 @@ import java.util.Arrays;
 import java.util.List;
 import java.util.concurrent.Executor;
 
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.Test;
 
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.context.annotation.Bean;
@@ -54,16 +53,14 @@ import org.springframework.messaging.PollableChannel;
 import org.springframework.messaging.SubscribableChannel;
 import org.springframework.messaging.support.MessageBuilder;
 import org.springframework.test.annotation.DirtiesContext;
-import org.springframework.test.context.ContextConfiguration;
-import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;
+import org.springframework.test.context.junit.jupiter.SpringJUnitConfig;
 
 /**
  * @author Artem Bilan
  * @author Gary Russell
  * @since 4.1
  */
-@ContextConfiguration
-@RunWith(SpringJUnit4ClassRunner.class)
+@SpringJUnitConfig
 @DirtiesContext
 public class ScatterGatherHandlerIntegrationTests {