Prevent inintended creation of OrderAuthor before ordering

When a grouped_order_detail view was called with authenticated user,
when prefilling the firstName, lastName and email also inserted a new
OrderAuthor object in the database.
Now use SimpleNamespace, instead of OrderAuthor object, to carry
those values to the template.

la_chariotte/order/views/grouped_order.py

@@ -1,5 +1,6 @@
 import csv
 import json
+from types import SimpleNamespace
 
 from django import http
 from django.contrib.auth.mixins import LoginRequiredMixin, UserPassesTestMixin
@@ -118,12 +119,11 @@ class GroupedOrderDetailView(generic.DetailView):
         prices_dict = {item.id: item.price for item in items}
 
         if self.request.user.is_authenticated:
-            order_author = OrderAuthor.objects.create(
+            order_author = SimpleNamespace(
                 first_name=self.request.user.first_name,
                 last_name=self.request.user.last_name,
                 email=self.request.user.username,
             )
-            order_author.save()
         else:
             order_author = None