[BANKCON-15711] Pass billing address and email address to payment details API

[mats-stripe]

Android equivalent: stripe/stripe-android#9446

Summary

This passes the billing address model and a billing email to the /consumers/payment_details/ API. More details: https://docs.google.com/document/d/1IP66DkxVK6DzeGCmuw00Gt9okFhEHQgM3lqBZSA-M4E/edit?usp=sharing

Note

There is currently a bug where the billing address is not being backfilled when using an existing Link account. This is being looked into (Slack), and can most likely be fixed with a backend change.

Motivation

BANKCON-15711

Testing

Unit tests, and I've verified the billing fields are correctly passed from MPE to the API call:

Changelog

N/a

[mats-stripe]

Source: https://stripe.sourcegraphcloud.com/stripe-internal/pay-server/-/blob/lib/consumer/api/methods/payment_details/create_payment_details.rb?L32-36

[mats-stripe]

Source: https://stripe.sourcegraphcloud.com/stripe-internal/pay-server/-/blob/lib/consumer/api/params/address.rb?L6:18-6:25

[github-actions]

🚨 New dead code detected in this PR:

FinancialConnectionsAPIClient.swift:246 warning: Function 'paymentDetails(consumerSessionClientSecret:bankAccountId:billingAddress:billingEmail:)' is unused

Please remove the dead code before merging.

If this is intentional, you can bypass this check by adding the label skip dead code check to this PR.

ℹ️ If this comment appears to be left in error, double check that the flagged code is actually used and/or make sure your branch is up-to-date with master.

[github-actions]

⚠️ Public API changes detected:

StripePaymentSheet

- public var paymentMethodLayout: StripePaymentSheet.PaymentSheet.PaymentMethodLayout
- public enum PaymentMethodLayout {
- case horizontal
- case vertical
- case automatic
- public static func == (a: StripePaymentSheet.PaymentSheet.PaymentMethodLayout, b: StripePaymentSheet.PaymentSheet.PaymentMethodLayout) -> Swift.Bool
- public func hash(into hasher: inout Swift.Hasher)
- public var hashValue: Swift.Int {
- get
- }
- }

If you are adding a new public API consider the following:

• Do these APIs need to be public or can they be protected with @_spi(STP)?
• If these APIs need to be public, assess whether they require an API review.

If you are modifying or removing a public API:

• Does this require a breaking version change?
• Do these changes require API review?

If you confirm these APIs need to be added/updated and have undergone necessary review, add the label modifies public API to this PR to acknowledge and bypass this check.

ℹ️ If this comment appears to be left in error, make sure your branch is up-to-date with master.