Fix logging stripe one time charge transactions (#469)

* Fix logging stripe one time charge transactions

Stripe's API probably changed sometime ago.

* fix tests

* fix tests - 2

Author: amCap1712

metabrainz/model/payment.py

@@ -310,8 +310,8 @@ def log_subscription_charge(cls, invoice):
     def log_one_time_charge(cls, session):
         """ Log successful Stripe charge for one time payment/donation """
         payment_intent = stripe.PaymentIntent.retrieve(session["payment_intent"],
-                                                       expand=["charges.data.balance_transaction"])
-        charge = payment_intent["charges"]["data"][0]
+                                                       expand=["latest_charge.balance_transaction"])
+        charge = payment_intent["latest_charge"]
         metadata = payment_intent["metadata"]
         return cls._log_stripe_charge(charge, metadata)