Fix: order chunks from docx by positions. (#7979)

### What problem does this PR solve?

#7934

### Type of change

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

rag/nlp/__init__.py

 def tokenize_chunks_with_images(chunks, doc, eng, images):
     res = []
     # wrap up as es documents
-    for ck, image in zip(chunks, images):
+    for ii, (ck, image) in enumerate(zip(chunks, images)):
         if len(ck.strip()) == 0:
             continue
         logging.debug("-- {}".format(ck))
         d = copy.deepcopy(doc)
         d["image"] = image
+        add_positions(d, [[ii]*5])
         tokenize(d, ck, eng)
         res.append(d)
     return res