Fix: docx parser output consistent (#12965)

### What problem does this PR solve?

Fix: docx parser output consistent

> File "/home/bxy/ragflow/rag/flow/parser/parser.py", line 506, in _word
>     sections, tbls = docx_parser(name, binary=blob)
>     ^^^^^^^^^^^^^^
> ValueError: too many values to unpack (expected 2)
> 

### Type of change

- [x] Bug Fix (non-breaking change which fixes an issue)

docs/references/http_api_reference.md

@@ -896,7 +896,7 @@ Success:
             "vector_similarity_weight": 0.3
         }
     ],
-    "total": 1
+    "total_datasets": 1
 }
 ```