[REG: 5.15.6->5.15.8] Qt Purchasing doesn't restore purchased products.

In 5.15.8 version QInAppStore::restorePurchases doesn't trigger transactionReady() signal for purchased products.

Code works well on 5.15.6.

iap_finalization.data contains list of purchased products. 

Code snippet provided by customer, according to them generates 5 "productRegistered" signals and after that 3 "transactionReady" signals for purchased products in 5.15.6. In 5.15.8 only 5 "productRegistered" signals.