Update app.py with correct data path

app.py

@@ -22,7 +22,7 @@ def init_models():
     )
     Settings.llm = llm
 
-    documents = SimpleDirectoryReader("Streamlit-LlamaIndex-API/data/README_zh-CN.md").load_data()
+    documents = SimpleDirectoryReader("./data").load_data()
     index = VectorStoreIndex.from_documents(documents)
     query_engine = index.as_query_engine()