fix bug reading pds4-labeled FITS files

Changes to the loaders.handlers.handle_fits_file() signature were not propagated to the PDS4 FITS-reading
workflow, causing failures when loading some objects. This simply removes the outdated id_as_offset argument
(handle_fits_file() now performs this behavior by default).

CHANGELOG.md

@@ -77,6 +77,7 @@ compatibility
 - The hotpatch for `pds4-tools` Python 3.12 incompatibility no longer
   has persistent side effects; for instance, `conda` will no longer
   complain about checksum mismatches.
+- bug reading PDS4-labeled FITS files
 
 ### Removed
 - `pdr.Data.__iter__` method is being deprecated

pdr/pdr.py

@@ -582,10 +582,7 @@ def _load_pds4(self, object_name: str):
 
             offset = structure.meta_data['offset']
             result = handle_fits_file(
-                structure.parent_filename,
-                object_name,
-                offset,
-                id_as_offset=True
+                structure.parent_filename, object_name, offset
             )
             if structure.is_header() is True:
                 return self._add_loaded_objects(result)