title: Stripe integration using actions-on-google generated payment token
body: <p>I have created actions on google application with transaction enabled. </p>
  
  <p>Upon successfully placing an order through assistant I am getting a payment token but it is a base64-encoded string and I dont know how to use it to charge the user using Stripe(payment gateway) api.</p>
  
  <p>in actions.intent.TRANSACTION_DECISION, I am getting response by doing :
  const arg = conv.arguments.get('TRANSACTION_DECISION_VALUE');</p>
  
  <p>The token I am getting is in this "arg" object :
  arg.order.paymentInfo.googleProvidedPaymentInstrument.instrumentToken</p>
  
  <p>Am I supposed to use this encoded token in Stripe or is there some other token?</p>
  
  <p>Thanks.</p>