Indicate the unique ID of the sender when testing "Message Auto Update Every 6 Secs"

Test: Manual
Bug: 135266377
Change-Id: I44bd7d3e7eadfcd27b8def41760c7a0a949ace6e
diff --git a/tests/EmbeddedKitchenSinkApp/src/com/google/android/car/kitchensink/notification/NotificationFragment.java b/tests/EmbeddedKitchenSinkApp/src/com/google/android/car/kitchensink/notification/NotificationFragment.java
index 7830449..e14b25f 100644
--- a/tests/EmbeddedKitchenSinkApp/src/com/google/android/car/kitchensink/notification/NotificationFragment.java
+++ b/tests/EmbeddedKitchenSinkApp/src/com/google/android/car/kitchensink/notification/NotificationFragment.java
@@ -359,7 +359,7 @@
             PendingIntent replyIntent = createServiceIntent(id, "reply");
             PendingIntent markAsReadIntent = createServiceIntent(id, "read");
 
-            Person person = new Person.Builder().setName("John Doe").build();
+            Person person = new Person.Builder().setName("John Doe " + id).build();
             MessagingStyle messagingStyle =
                     new MessagingStyle(person).setConversationTitle("Hello!");
             NotificationCompat.Builder builder = new NotificationCompat