Adding newline to onos-app plugin because json output doesn't contain one

Change-Id: I55286436cfa819355aa7fbea55c0908053ce45a7
diff --git a/tools/test/bin/onos-app b/tools/test/bin/onos-app
index 268fb1b..58b6c08 100755
--- a/tools/test/bin/onos-app
+++ b/tools/test/bin/onos-app
@@ -48,3 +48,5 @@
 
     *) usage;;
 esac
+
+echo #new line for prompt