From the release notes:
Apple Clang Compiler
Known Issues
Apps built with Xcode 13 or Xcode 13.1 that make use of Swift Concurrency features (such as async/await), deploy to iOS prior to 15, tvOS prior to 15, or watchOS prior to 8, and have bitcode enabled may crash at launch with an error reporting that the libswift_Concurrency.dylib library was not loaded. (86349088)
Workaround: Add -Wl,-weak-lswift_Concurrency -Wl,-rpath,/usr/lib/swift to Other Linker Flags in the app’s build settings.