HttpResponseForbidden -> PermissionDenied

Thi is necessary to properly render 403 template.

issue/middleware.py

@@ -1,6 +1,6 @@
 from django.core.exceptions import ImproperlyConfigured
 from django.core.exceptions import ObjectDoesNotExist
-from django.http import HttpResponseForbidden
+from django.core.exceptions import PermissionDenied
 from django.contrib.auth.decorators import login_required
 from django.db.models import Q
 
@@ -56,7 +56,7 @@ class ProjectMiddleware:
             project = projects.get(name=project)
         except ObjectDoesNotExist:
             if request.user.is_authenticated():
-                return HttpResponseForbidden()
+                raise PermissionDenied()
             else:
                 return login_required(view)(request, *view_args, **view_kwargs)
         view_kwargs['project'] = project