[mirotalksfu] - add share file btn to chat

public/view/Room.html

@@ -364,6 +364,9 @@ access to use this app.
                     <button id="chatEmojiButton" class="hidden">
                         <i class="fas fa-smile"></i>
                     </button>
+                    <button id="chatShareFileButton" class="hidden">
+                        <i class="fas fa-file"></i>
+                    </button>
                     <button id="chatSpeechStartButton" class="hidden">
                         <i class="fas fa-microphone-slash"></i>
                     </button>