Remove more Python 3.8 cruft (#13787)

stdlib/array.pyi

@@ -1,14 +1,10 @@
 import sys
 from _typeshed import ReadableBuffer, SupportsRead, SupportsWrite
-from collections.abc import Iterable
-
-# pytype crashes if array inherits from collections.abc.MutableSequence instead of typing.MutableSequence
-from typing import Any, ClassVar, Literal, MutableSequence, SupportsIndex, TypeVar, overload  # noqa: Y022
+from collections.abc import Iterable, MutableSequence
+from types import GenericAlias
+from typing import Any, ClassVar, Literal, SupportsIndex, TypeVar, overload
 from typing_extensions import Self, TypeAlias
 
-if sys.version_info >= (3, 12):
-    from types import GenericAlias
-
 _IntTypeCode: TypeAlias = Literal["b", "B", "h", "H", "i", "I", "l", "L", "q", "Q"]
 _FloatTypeCode: TypeAlias = Literal["f", "d"]
 _UnicodeTypeCode: TypeAlias = Literal["u"]