CC-4356: Improved method of detecting RabbitMQ PID

-fixed

utils/rabbitmq-update-pid.sh

@@ -5,8 +5,7 @@ pid_found="$?"
 
 if [ "$pid_found" == "0" ]; then
     #PID is available in the status message
-    rabbitmqstatus=`/etc/init.d/rabbitmq-server status | grep "\[{pid"`
-    rabbitmqpid=`echo $rabbitmqstatus | sed "s/.*,\(.*\)\}.*/\1/"`
+    rabbitmqpid=`/etc/init.d/rabbitmq-server status | grep "\[{pid" | sed "s/.*,\(.*\)\}.*/\1/"`
 else
     #PID should be available from file
     rabbitmqpid=`sed "s/.*,\(.*\)\}.*/\1/" /var/lib/rabbitmq/pids`