[in_app_purchase_storekit] Add Swift Package Manager compatibility#8469

auto-submit[bot] merged 13 commits intoflutter:mainflutter/packages:mainfrom

alejandro-all-win-software:feat/in-app-purchase-add-swift-package-manager-supportalejandro-all-win-software/packages:feat/in-app-purchase-add-swift-package-manager-supportCopy head branch name to clipboard