Remove sub subquery alias notneeded

Author: nabinchha

src/data_designer/engine/column_generators/generators/seed_dataset.py

@@ -101,7 +101,7 @@ def _reset_batch_reader(self, num_records: int) -> None:
                 SELECT * EXCLUDE (row_num) FROM (
                     SELECT *, row_number() OVER () as row_num
                     FROM '{self._dataset_uri}'
-                ) sub
+                )
                 WHERE row_num > {self._index_range.start} AND row_num <= {self._index_range.end + 1}
                 {shuffle_query}
             """