Update PaymentIntent.swift (#256)

Co-authored-by: Andrew Edwards <[email protected]>

Sources/StripeKit/Core Resources/PaymentIntents/PaymentIntent.swift

@@ -238,6 +238,7 @@ public enum PaymentIntentCancellationReason: String, Codable {
 public enum PaymentIntentCaptureMethod: String, Codable {
     /// (Default) Stripe automatically captures funds when the customer authorizes the payment.
     case automatic
+    case automaticAsync = "automatic_async"
     /// Place a hold on the funds when the customer authorizes the payment, but don’t capture the funds until later. (Not all payment methods support this.)
     case manual
 }