Don't set custom callbackQueue for underlying Websocket

Author: hamchapman

Source/PusherSwift.swift

@@ -40,7 +40,6 @@ let CLIENT_NAME = "pusher-websocket-swift"
         self.key = key
         let urlString = constructUrl(key: key, options: options)
         let ws = WebSocket(url: URL(string: urlString)!)
-        ws.callbackQueue = DispatchQueue(label: "com.pusher.starscream.websocket.callback")
         connection = PusherConnection(key: key, socket: ws, url: urlString, options: options)
         connection.createGlobalChannel()
         self.nativePusher = nativePusher