fix(langgraph): remove deprecated output usage in favor of output_schema (#5095)

use output_schema

libs/prebuilt/tests/test_react_agent.py

@@ -1089,14 +1089,17 @@ def test_react_with_subgraph_tools(
         return {"result": state["a"] + state["b"]}
 
     add_subgraph = (
-        StateGraph(State, output=Output).add_node(add).add_edge(START, "add").compile()
+        StateGraph(State, output_schema=Output)
+        .add_node(add)
+        .add_edge(START, "add")
+        .compile()
     )
 
     def multiply(state):
         return {"result": state["a"] * state["b"]}
 
     multiply_subgraph = (
-        StateGraph(State, output=Output)
+        StateGraph(State, output_schema=Output)
         .add_node(multiply)
         .add_edge(START, "multiply")
         .compile()