PaywallActivity doesn't implement all methods in PaywallListener

[Xendrez]

• [x] I have updated Purchases SDK to the latest version
• [x] I have read the Contribution Guidelines
• [x] I have searched the Community
• [x] I have read docs.revenuecat.com
• [x] I have searched for existing Github issues

Describe the bug The current PaywallActivity (ui/revenuecatui/src/main/kotlin/com/revenuecat/purchases/ui/revenuecatui/activity/PaywallActivity.kt) does not implement all the methods in the PaywallListener (ui/revenuecatui/src/main/kotlin/com/revenuecat/purchases/ui/revenuecatui/PaywallListener.kt). The result is that if the user taps on 'restore', nothing happens. (And nothing can happen as I don't get a result from the Activity). The same is true for the PurchaseError when, for example the user already owns the product.

1. Environment

   1. Platform: Android
   2. SDK version:
   3. OS version:
   4. Android Studio version:
   5. How widespread is the issue. Percentage of devices affected.

2. Debug logs that reproduce the issue

3. Steps to reproduce:

   1. Implement the paywall using the Activity as documented here: https://www.revenuecat.com/docs/displaying-paywalls#how-to-display-a-fullscreen-paywall-in-your-app-1
   2. Expect to get all results for PaywallListener like here: ui/revenuecatui/src/main/kotlin/com/revenuecat/purchases/ui/revenuecatui/PaywallListener.kt
   3. Instead, only get result when a successful new purchase is made.

4. Other information (e.g. stacktraces, related issues, suggestions how to fix, links for us to have context, eg. stackoverflow, etc.)

Additional context Add any other context about the problem here.