make use of parameter with_notification

shop_paypal/payment.py

@@ -125,7 +125,7 @@ def return_view(cls, request):
             order = OrderModel.objects.create_from_cart(cart, request)
             order.populate_from_cart(cart, request)
             order.add_paypal_payment(payment.to_dict())
-            order.save()
+            order.save(with_notification=True)
             return HttpResponseRedirect(order.get_absolute_url())
         return cls.cancel_view(request)