Expose MessageProducerSpec.role(String) option

Related to: https://stackoverflow.com/questions/78294542/role-in-integrationflow-dsl

**Auto-cherry-pick to `6.2.x` & `6.1.x`**

spring-integration-core/src/main/java/org/springframework/integration/dsl/MessageProducerSpec.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2016-2023 the original author or authors.
+ * Copyright 2016-2024 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.
@@ -70,6 +70,20 @@ public abstract class MessageProducerSpec<S extends MessageProducerSpec<S, P>, P
 		return _this();
 	}
 
+	/**
+	 * Specify the role for the endpoint.
+	 * Such endpoints can be started/stopped as a group.
+	 * @param role the role for this endpoint.
+	 * @return the endpoint spec
+	 * @see org.springframework.context.SmartLifecycle
+	 * @see org.springframework.integration.support.SmartLifecycleRoleController
+	 * @since 6.1.8
+	 */
+	public S role(String role) {
+		this.target.setRole(role);
+		return _this();
+	}
+
 	/**
 	 * Specify the {@code outputChannel} for the
 	 * {@link org.springframework.integration.core.MessageProducer}.

spring-integration-jms/src/test/java/org/springframework/integration/jms/dsl/JmsTests.java

@@ -534,6 +534,7 @@ public class JmsTests extends ActiveMQMultiContextTests {
 		public IntegrationFlow jmsMessageDrivenRedeliveryFlow() {
 			return IntegrationFlow
 					.from(Jms.messageDrivenChannelAdapter(amqFactory)
+							.role("someRole")
 							.errorChannel("errorChannelForRedelivery")
 							.destination("jmsMessageDrivenRedelivery")
 							.configureListenerContainer(c -> c