fix style

Author: lhoestq

src/datasets/utils/metadata.py

@@ -2,7 +2,7 @@
 import logging
 import re
 from collections import Counter
-from dataclasses import asdict, dataclass, fields
+from dataclasses import dataclass, fields
 from pathlib import Path
 from typing import Any, Callable, ClassVar, Dict, List, Optional, Tuple, Type, Union