Make data input to _compose_parser optional

This allows `g` aka `_create_register_reader` to take care of the path inference logic

Author: bruno-f-cruz

harp/reader.py

@@ -82,7 +82,7 @@ def _compose_parser(
     params: _ReaderParams,
 ) -> Callable[..., DataFrame]:
     def parser(
-        data,
+        data: Optional[Union[_FileLike, _BufferLike]] = None,
         columns: Optional[Axes] = None,
         epoch: Optional[datetime] = params.epoch,
         keep_type: bool = params.keep_type,