fix(presenter-mode): Look up presenter track using type 'video'

modules/RTC/JitsiLocalTrack.js

             }
 
             promise.then(streamsInfo => {
-                // Do not add the presenter track to the conference
-                if (this.getType() === 'presenter') {
-                    return Promise.resolve();
-                }
-                const mediaType = this.getType();
+                // The track kind for presenter track is video as well.
+                const mediaType = this.getType() === MediaType.PRESENTER ? MediaType.VIDEO : this.getType();
                 const streamInfo
                     = browser.usesNewGumFlow()
                         ? streamsInfo.find(

service/RTC/MediaType.js

  */
 export const AUDIO = 'audio';
 
+/**
+ * The presenter type.
+ */
+export const PRESENTER = 'presenter';
+
 /**
  * The video type.
  */