Fix ruff errors

Author: asmeurer

array_api_compat/common/_aliases.py

@@ -7,7 +7,7 @@
 from typing import TYPE_CHECKING
 if TYPE_CHECKING:
     from typing import Optional, Sequence, Tuple, Union
-    from ._typing import ndarray, Device, Dtype, NestedSequence, SupportsBufferProtocol
+    from ._typing import ndarray, Device, Dtype
 
 from typing import NamedTuple
 import inspect

array_api_compat/numpy/__init__.py

@@ -23,7 +23,7 @@
 
 try:
     # Used in asarray(). Not present in older versions.
-    from numpy import _CopyMode
+    from numpy import _CopyMode # noqa: F401
 except ImportError:
     pass