reset chat history when clear

app.py

@@ -121,6 +121,7 @@ with gr.Blocks() as demo:
 
     clear.click(lambda: None, None, chatbot, queue=False)
     clear.click(lambda: None, None, session_id, queue=False)
+    clear.click(lambda: None, None, state, queue=False)
 
     send.click(respond, [chatbot, message, state, session_id, user_serial, persona, context, endpoint], [chatbot, state, status_box, session, session_id])
     send.click(reset_textbox, [], [message])