Upgrade to ActiveMQ-5.15.0 and increase test time

https://build.spring.io/browse/INTSAMPLES-NIGHTLY-2211

It isn't clear why second message copy is lost, so increase timeout
in case of some fluctuations in the ActiveMQ.
Also increase logging level to DEBUG to see some info in the next failure

basic/jms/src/main/resources/META-INF/spring/integration/aggregation.xml

@@ -28,7 +28,7 @@
 	<int:channel id="jmsReplyChannel" />
 
 	<int:aggregator input-channel="jmsReplyChannel" output-channel="out"
-		group-timeout="20000"
+		group-timeout="40000"
 		expire-groups-upon-timeout="false"
 		send-partial-result-on-expiry="true"
 		discard-channel="logLateArrivers"

basic/jms/src/main/resources/log4j2.xml

@@ -10,7 +10,7 @@
 			<AppenderRef ref="Console" />
 		</Root>
 		<Logger name="org.springframework" level="warn" />
-		<Logger name="org.springframework.integration" level="warn" />
+		<Logger name="org.springframework.integration" level="debug" />
 		<Logger name="org.springframework.integration.samples" level="debug" />
 	</Loggers>
 </Configuration>

build.gradle

@@ -169,7 +169,7 @@ subprojects { subproject ->
 		}
 
 		ext {
-			activeMqVersion = '5.13.4'
+			activeMqVersion = '5.15.0'
 			apacheSshdVersion = '1.4.0'
 			aspectjVersion = '1.8.9'
 			commonsDigesterVersion = '2.0'