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

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

src/tox/config/loader/toml/__init__.py

@@ -1,7 +1,7 @@
 from __future__ import annotations
 
 from pathlib import Path
-from typing import TYPE_CHECKING, Dict, Iterator, List, Mapping, Set, TypeVar, cast
+from typing import TYPE_CHECKING, Dict, Iterator, List, Mapping, TypeVar, cast
 
 from tox.config.loader.api import ConfigLoadArgs, Loader, Override
 from tox.config.types import Command, EnvList