fix: Support for Safari (desktop ... iOS?)

[nfreear]

..

1. "TypeError: function is not a constructor (evaluating 'super()')"

   • SpeechRecognition - createDict...js:122

2. "Error: Browser does not support Web Audio API (AudioContext is not available)."

   • https://github.com/microsoft/BotFramework-WebChat/blob/master/packages/bundle/src/createCognitiveServicesSpeechServicesPonyfillFactory.js#L57-L99;

..