GH-1352: Fix Test Container

spring-rabbit/src/main/java/org/springframework/amqp/rabbit/listener/AbstractMessageListenerContainer.java

@@ -457,6 +457,7 @@ public abstract class AbstractMessageListenerContainer extends RabbitAccessor
 	/**
 	 * @return The message listener object to register.
 	 */
+	@Override
 	public Object getMessageListener() {
 		return this.messageListener;
 	}
@@ -557,6 +558,7 @@ public abstract class AbstractMessageListenerContainer extends RabbitAccessor
 	 *
 	 * @param autoStartup true for auto startup.
 	 */
+	@Override
 	public void setAutoStartup(boolean autoStartup) {
 		this.autoStartup = autoStartup;
 	}

spring-rabbit/src/test/java/org/springframework/amqp/rabbit/config/MessageListenerTestContainer.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2019 the original author or authors.
+ * Copyright 2002-2021 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.
@@ -21,6 +21,7 @@ import org.springframework.amqp.rabbit.listener.MessageListenerContainer;
 import org.springframework.amqp.rabbit.listener.RabbitListenerEndpoint;
 import org.springframework.beans.factory.DisposableBean;
 import org.springframework.beans.factory.InitializingBean;
+import org.springframework.lang.Nullable;
 
 /**
  * @author Stephane Nicoll
@@ -47,6 +48,16 @@ public class MessageListenerTestContainer
 		return endpoint;
 	}
 
+	@Override
+	public void setAutoStartup(boolean autoStart) {
+	}
+
+	@Override
+	@Nullable
+	public Object getMessageListener() {
+		return null;
+	}
+
 	public boolean isStarted() {
 		return startInvoked && initializationInvoked;
 	}