refactor: comment out clean_memory function call

- Remove the call to clean_memory() function from pdf_parse_union_core_v2.py
- This change may affect memory usage and needs to be tested to ensure proper functionality

magic_pdf/pdf_parse_union_core_v2.py

@@ -825,7 +825,7 @@ def pdf_parse_union(
         'pdf_info': pdf_info_list,
     }
 
-    clean_memory()
+    # clean_memory()
 
     return new_pdf_info_dict