[pre-commit.ci] auto fixes from pre-commit.com hooks

for more information, see https://pre-commit.ci

Author: pre-commit-ci[bot]

monai/data/dataset.py

@@ -22,7 +22,6 @@
 import warnings
 from collections.abc import Callable, Sequence
 from copy import copy, deepcopy
-from inspect import signature
 from multiprocessing.managers import ListProxy
 from multiprocessing.pool import ThreadPool
 from pathlib import Path