message: Add receipt_url field to the charge object
diff: @@ -296,6 +296,7 @@ pub struct Charge {
  pub outcome: Option<ChargeOutcome>,
  pub paid: bool,
  pub payment_intent: Option<String>,
  + pub receipt_url: Option<String>,
  pub receipt_email: Option<String>,
  pub receipt_number: Option<String>,
  pub refunded: bool,
  