Follow up to #1557. Subtask of #1382
### Description
This PR aims to clear the stuff in the cache when the Storefront changes.
Changes:
- Add `clearCachedOfferings` method to `DeviceCache`.
- Add `clearCache` method to `ProductFetcherSK1`.
- Make `internal` the `clearCache` method in `ProductsFetcherSK2`.
- Handle the **Storefront** changes in the `PurchasesOrchestator`.
- Add tests to cover some scenarios.
Fixes [SDKONCALL-19].
SK2 purchases were always calling `syncPurchases`, which called `Backend.post(receiptData:...)` with no `productData`, which meant that after every SK2 purchase we never posted the price.
This refactor makes a lot of methods in `PurchasesOrchestrator` use `StoreTransaction` so they can be used during SK2 purchases as well. Specifically, `handlePurchasedTransaction` is now called after both SK1 and SK2 purchases.
### Other changes:
- `StoreKit2TransactionListenerDelegate` no longer needs to return `CustomerInfo`
- `StoreKit2TransactionListenerDelegate.handle(purchaseResult:)` no longer notifies the delegate (only done by `StoreKit.Transaction.updates`), which was leading to duplicate `syncPurchases` calls.
- If the purchase is cancelled, `syncPurchases` isn't called. Instead, the `CustomerInfo` is fetched from `CustomerInfoManager`
[SDKONCALL-19]: https://revenuecats.atlassian.net/browse/SDKONCALL-19?atlOrigin=eyJpIjoiNWRkNTljNzYxNjVmNDY3MDlhMDU5Y2ZhYzA5YTRkZjUiLCJwIjoiZ2l0aHViLWNvbS1KU1cifQ
* Listen changes via `paymentQueueDidChangeStorefront` method
* Create `StoreKit2StorefrontListener.swift` to listen to Storefront changes for SK2
* Update `PurchasesOrchestrator` to listen to the Storefront changes
* Include `StoreKit2StorefrontListenerTests` in StoreKitTests
Co-authored-by: NachoSoto <NachoSoto@users.noreply.github.com>
* Remove force unwrap
Co-authored-by: NachoSoto <NachoSoto@users.noreply.github.com>
* Add required spaces
Co-authored-by: NachoSoto <NachoSoto@users.noreply.github.com>
* Remove useless cancel method when the listener is released
* Notify Storefront changes in the main thread
* Add cancel task when the Listener is released
Co-authored-by: NachoSoto <NachoSoto@users.noreply.github.com>
`StoreKit2TransactionListener` was triggering an asynchronous call to `syncPurchases` during transaction verification, and at the end of every purchase, another `syncPurchases` call was being made.
This refactor combines both calls into one by making `finish(transaction:)` wait for that call to finish.
Juanpe Catalán