After deploy to iTunes Connect / TestFlight Apple sent an email:
We have discovered one or more issues with your recent delivery for “X”. To process your delivery, the following issues must be corrected:
Invalid Swift Support - The SwiftSupport folder is missing. Rebuild your app using the current public (GM) version of Xcode and resubmit it.
Once these issues have been corrected, you can then redeliver the corrected binary.
The App Store team