message: feat: fn to expire checkout sessions
diff: @@ -14,4 +14,11 @@ impl CheckoutSession {
  ) -> Response<CheckoutSession> {
  client.get_query(&format!("/checkout/sessions/{}", id), &Expand { expand })
  }
  +
  + /// Expires a checkout session.
  + ///
  + /// For more details see <https://stripe.com/docs/api/checkout/sessions/expire>.
  + pub fn expire(client: &Client, id: &CheckoutSessionId) -> Response<CheckoutSession> {
  + client.post(&format!("/checkout/sessions/{}/expire", id))
  + }
  }
  