only support numpy datetime64 in ScalarType

Author: brokkoli71

src/zarr/core/buffer/core.py

@@ -1,6 +1,5 @@
 from __future__ import annotations
 
-import datetime
 import sys
 from abc import ABC, abstractmethod
 from typing import (
@@ -107,9 +106,7 @@ def __eq__(self, other: object) -> Self:  # type: ignore[explicit-override, over
         """
 
 
-ScalarType = (
-    int | float | complex | bytes | str | bool | datetime.datetime | datetime.timedelta | np.generic
-)
+ScalarType = int | float | complex | bytes | str | bool | np.generic
 NDArrayOrScalarLike = ScalarType | NDArrayLike