Minor cleanup (apache#2298)

# Rationale for this change

Missed this in another PR

# Are these changes tested?

# Are there any user-facing changes?

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Author: Fokko

pyiceberg/io/pyarrow.py

@@ -1492,16 +1492,14 @@ def _task_to_record_batches(
 
                 current_batch = table.combine_chunks().to_batches()[0]
 
-            result_batch = _to_requested_schema(
+            yield _to_requested_schema(
                 projected_schema,
                 file_project_schema,
                 current_batch,
                 downcast_ns_timestamp_to_us=True,
                 projected_missing_fields=projected_missing_fields,
             )
 
-            yield result_batch
-
 
 def _read_all_delete_files(io: FileIO, tasks: Iterable[FileScanTask]) -> Dict[str, List[ChunkedArray]]:
     deletes_per_file: Dict[str, List[ChunkedArray]] = {}