Upgrade amqp-client to 5.4.1

Author: garyrussell

build.gradle

@@ -82,7 +82,7 @@ subprojects { subproject ->
 		log4jVersion = '2.11.0'
 		logbackVersion = '1.2.3'
 		mockitoVersion = '2.18.0'
-		rabbitmqVersion = project.hasProperty('rabbitmqVersion') ? project.rabbitmqVersion : '5.4.0.RC2'
+		rabbitmqVersion = project.hasProperty('rabbitmqVersion') ? project.rabbitmqVersion : '5.4.1'
 		rabbitmqHttpClientVersion = '2.1.0.RELEASE'
 
 		springVersion = project.hasProperty('springVersion') ? project.springVersion : '5.1.0.RC2'