Fix build in release

[JustinMeans]

The following fixes are proposed to enable the library to compile in release mode.

Thanks for creating this library!

This was the build error given when compiling in release prior to these changes:

/Users/justinmeans/Downloads/websocket-actor-system/Sources/WebSocketActors/Continuation.swift:33:58: error: extra argument in call
        await withUnsafeContinuation(function: function, body)
                                    ~~~~~~~~~~~~~~~~~~~~~^~~~~
/Users/justinmeans/Downloads/websocket-actor-system/Sources/WebSocketActors/Continuation.swift:33:48: error: cannot convert value of type 'String' to expected argument type '(UnsafeContinuation<T, Never>) -> Void'
        await withUnsafeContinuation(function: function, body)
                                               ^
/Users/justinmeans/Downloads/websocket-actor-system/Sources/WebSocketActors/Continuation.swift:39:70: error: extra argument in call
        try await withUnsafeThrowingContinuation(function: function, body)
                                                ~~~~~~~~~~~~~~~~~~~~~^~~~~
/Users/justinmeans/Downloads/websocket-actor-system/Sources/WebSocketActors/Continuation.swift:39:60: error: cannot convert value of type 'String' to expected argument type '(UnsafeContinuation<T, any Error>) -> Void'
        try await withUnsafeThrowingContinuation(function: function, body)