nt signals that the service has stopped processing speech.
            // https://docs.microsoft.com/javascript/api/microsoft-cognitiveservices-speech-sdk/speechrecognitioncanceledeventargs?view=azure-node-latest
            // This can happen for two broad classes of reasons:
            // 1. An error was encountered.
            //    In this case, the .errorDetails property will contain a textual representation of the error.
            // 2. No additional audio is available.
            //    This is c