Make ConditionallySeekable a Protocol

Author: nateprewitt

packages/aws-sdk-signers/src/aws_sdk_signers/interfaces/io.py

@@ -37,7 +37,7 @@ def tell(self) -> int: ...
 
 
 @runtime_checkable
-class ConditionallySeekable:
+class ConditionallySeekable(Protocol):
     """A file-like object that is conditionally seekable.
 
     This is separate from Seekable and AsyncSeekable as seekable objects may not define