Fix: parent-children chunking method. (#11997)

### Type of change

- [x] Bug Fix (non-breaking change which fixes an issue)
- [x] New Feature (non-breaking change which adds functionality)

api/apps/chunk_app.py

@@ -386,6 +386,7 @@ async def retrieval_test():
                                                    LLMBundle(kb.tenant_id, LLMType.CHAT))
             if ck["content_with_weight"]:
                 ranks["chunks"].insert(0, ck)
+        ranks["chunks"] = settings.retriever.retrieval_by_children(ranks["chunks"], tenant_ids)
 
         for c in ranks["chunks"]:
             c.pop("vector", None)