Have you found a solution? I'm facing this problem right now and I need to fix this problem to can implement in app purchases

You still can deploy your apps on App Store and TestFlight. The unique thing you need is Xcode Cloud. You can build your app and download an Archive to submit it later to App Store Connect. See documentation of how to use Xcode Cloud, create workflow, etc https://developer.apple.com/xcode-cloud/get-started/. To download archive just open a build logs after it finish on Xcode Cloud and find the button "Artifacts". Click it and download Archive