message: Add PaymentIntentCanceled event type
diff: @@ -136,6 +136,8 @@ pub enum EventType {
  OrderReturnUpdated,
  #[serde(rename = "payment_intent.amount_capturable_updated")]
  PaymentIntentAmountCapturableUpdated,
  + #[serde(rename = "payment_intent.canceled")]
  + PaymentIntentCanceled,
  #[serde(rename = "payment_intent.created")]
  PaymentIntentCreated,
  #[serde(rename = "payment_intent.payment_failed")]
  