Add tests for the events_for_object view and fix the content type of the same view response.

Fixes GitLab issue #311 for the events link.

mayan/apps/events/apps.py

@@ -15,6 +15,7 @@ from .widgets import event_type_link
 
 class EventsApp(MayanAppConfig):
     name = 'events'
+    test = True
     verbose_name = _('Events')
 
     def ready(self):

mayan/apps/events/views.py

@@ -43,16 +43,16 @@ class ObjectEventListView(EventListView):
     view_permissions = None
 
     def dispatch(self, request, *args, **kwargs):
-        self.content_type = get_object_or_404(
+        self.object_content_type = get_object_or_404(
             ContentType, app_label=self.kwargs['app_label'],
             model=self.kwargs['model']
         )
 
         try:
-            self.content_object = self.content_type.get_object_for_this_type(
+            self.content_object = self.object_content_type.get_object_for_this_type(
                 pk=self.kwargs['object_id']
             )
-        except self.content_type.model_class().DoesNotExist:
+        except self.object_content_type.model_class().DoesNotExist:
             raise Http404
 
         try: