avoid slave lag since we call update after a write (bug 583367)

apps/reviews/tasks.py

@@ -20,7 +20,7 @@ def update_denorm(*pairs, **kw):
     log.info('[%s@%s] Updating review denorms.' %
              (len(pairs), update_denorm.rate_limit))
     for addon, user in pairs:
-        reviews = list(Review.objects.valid().no_cache()
+        reviews = list(Review.objects.valid().no_cache().using('default')
                        .filter(addon=addon, user=user)
                        .filter(reply_to=None).order_by('created'))
         if not reviews: