Update app.py

app.py

@@ -305,7 +305,7 @@ def create_agent_executor(llm, tools: List[Tool], tracer: Optional[Any] = None)
     return executor
 
 # -------------------- GAIA Runner --------------------
-class GaiaRunner
+class GaiaRunner:
 
     def __init__(self, agent_executor: AgentExecutor, username: str = "unknown"):
         self.agent = agent_executor