cancel specific notification if there is an identifier

Session/Notifications/AppNotifications.swift

@@ -139,7 +139,11 @@ public class NotificationPresenter: NSObject, NotificationsProtocol {
         switch notification.object {
         case let incomingMessage as TSIncomingMessage:
             Logger.debug("canceled notification for message: \(incomingMessage)")
+            if let identifier = incomingMessage.notificationIdentifier {
+                cancelNotification(identifier)
+            } else {
                 cancelNotifications(threadId: incomingMessage.uniqueThreadId)
+            }
         default:
             break
         }