[NT-261] Pass refParam with Apple Pay backings

[ifbarrera]

📲 What

Passes through the refTag from the project page all the way to the createApplePayBacking request.

🤔 Why

So we can track the referrer on Apple Pay backings.

🛠 How

Passes the RefTag from the project page to the PledgeViewController, which then passes it as part of the mutation input for the createApplePayBacking mutation. The refTag is always optional.

✅ Acceptance criteria

To test Apple Pay transactions, you must run the app on a device that is Apple Pay capable.

• On Staging, with the Native Checkout and Native Pledge Screen feature flags turned ON, from "Discovery", navigate to any project and select any reward. You should see the "Apple Pay" button. Tap the "Apple Pay" button and complete the transaction. In the console, you should see ⚪️ [KsApi] Input: which will show you the mutation input for the createApplePayBacking mutation. In the input, you should see the key refParam.

[dusi]

Works like a charm

Approved even though I had 1 question (feel free to ping me back if you're going to address it or not - I can do a quick re-review).

Those test descriptions were super helpful, thank you for providing those!

[dusi]

Should we also inject refTag from ManageViewPledgeViewController or is it not going to be necessary?

[ifbarrera]

Hmmm, I think it's not necessary. The updateBackingPaymentSource mutation doesn't currently accept a refParam. I'd imagine that for updating your backing, the backend would automatically set the referrer as update_pledge or something like that, since there's no real "referrer" for updating a pledge. I'll double check with product though. Regardless I think if we wanted to pass the refParam with the updateBackingPaymentSource mutation that would be in a separate PR.

[dusi]

I like this!