Fix lint errors

Author: tswast

bigquery/google/cloud/bigquery/dbapi/cursor.py

@@ -198,7 +198,6 @@ def _try_fetch(self, size=None):
             self._query_data = iter(
                 self._query_results.fetch_data(max_results=size))
 
-
     def fetchone(self):
         """Fetch a single row from the results of the last ``execute*()`` call.