An asynchronous failable initializer Loads the Customer's payment methods, their default payment method, etc.
Configuration for the PaymentSheet. e.g. your business name, customer details, etc.
A valid EmbeddedPaymentElement instance if successful, null otherwise.
If loading fails, this function sets the loadingError state variable instead of throwing an error.
An asynchronous failable initializer Loads the Customer's payment methods, their default payment method, etc.