[Apple Pay] Hide Apple Pay for unsupported project countries

[ifbarrera]

📲 What

Apple Pay is only supported a subset of countries that Kickstarter has launched in, so we should hide the Apple Pay button if the project is in a country that is not supported.

🤔 Why

Apple Pay.

🛠 How

Apple Pay is only supported in a subset of countries that Kickstarter has launched in. We get this list of countries from the /config endpoint. In addition to checking whether the user's device has the Apple Pay capability, as also determine whether Kickstarter supports Apple Pay in the project's country.

✅ Acceptance criteria

With the Native Checkout and Native Pledge Screen feature flags turned ON

• Run the app on a device that has Apple Pay set up. Navigate to a project in the US. You should see the Apple Pay button on the new pledge screen.
• Run the app on a device that has Apple Pay set up. Navigate to a project in Mexico (not supported). You should not see the Apple Pay button on the new pledge screen.

[Scollaco]

Nice job, @ifbarrera ! I just left a couple comments/suggestions