use pk instead of id in clear expired tokens

Author: sahama

oauth2_provider/models.py

@@ -712,9 +712,9 @@ def batch_delete(queryset, query):
         current_no = start_no = queryset.count()
 
         while current_no:
-            flat_queryset = queryset.values_list("id", flat=True)[:CLEAR_EXPIRED_TOKENS_BATCH_SIZE]
+            flat_queryset = queryset.values_list("pk", flat=True)[:CLEAR_EXPIRED_TOKENS_BATCH_SIZE]
             batch_length = flat_queryset.count()
-            queryset.model.objects.filter(id__in=list(flat_queryset)).delete()
+            queryset.model.objects.filter(pk__in=list(flat_queryset)).delete()
             logger.debug(f"{batch_length} tokens deleted, {current_no - batch_length} left")
             queryset = queryset.model.objects.filter(query)
             time.sleep(CLEAR_EXPIRED_TOKENS_BATCH_INTERVAL)