OnPurchaseFailed fires with DuplicateTransaction when ConfirmPurchase is called on NonConsumable products

How to reproduce:
1. Open the attached “Duck99 (1) 2.zip” project
2. Set up the environment by following this guide: https://docs.unity3d.com/Packages/com.unity.purchasing@4.12/manual/UnityIAPAppleConfiguration.html
3. Build to a device
4. Complete the game tutorial
5. In the bottom-right corner, click the three-dot menu
6. In the expanded menu, click the “Shop” button
7. Purchase the item that invokes ConfirmPurchase
8. Observe the Xcode console

Actual result: ConfirmPurchase succeeds without any further callbacks
Expected result: OnPurchaseFailed with DuplicateTransaction fires shortly after ConfirmPurchase

Reproducible with: 5.1.1 (6000.3.2f1)

Reproducible environment: Windows 11 (Reporter)
Not reproducible environment: No other environments tested

Note: Not tested by the CQA