I found that the solution is using the Xcode 13.3 beta (I specifically used beta 3).

Did you ever solve this? I am running into the same error on macOS and iOS versions of an app I am developing (currently using 15.4 beta and 12.3 beta)... This only happens if I reference the async await version of URLSessionWebSocketTask.send(_:), the crash occurs whether or not it actually gets called. The same happens for URLSessionWebSocketTask.receive(). Strangely the non async/await versions of these do work (URLSessionWebSocketTask.send(_:completionHandler:) and URLSessionWebSocketTask.receive(completionHandler:)).