notify other participants on session leave

on leaving the session directly delete the participant record and
notify other clients ref: VRFS-5529

web/app/assets/javascripts/react-components/stores/SessionStore.js.coffee

@@ -1952,7 +1952,7 @@ ConfigureTracksActions = @ConfigureTracksActions
           this.rateSessionDialog.showDialog();
         }
 
-        this.leaveSession();
+        await this.leaveSession();
         await this.sessionUtils.SessionPageLeave();
       }`
 
@@ -1968,15 +1968,15 @@ ConfigureTracksActions = @ConfigureTracksActions
     #       @performLeaveSession(deferred)
     #     )
 
-    leaveSession: `function() {
-
+    leaveSession: `async function() {
         if ((this.joinDeferred == null) || this.isJoinDeferredResolved) {
           const deferred = new $.Deferred();
           const self = this;
-          Promise.resolve(this.recordingModel.stopRecordingIfNeeded())
+          /*Promise.resolve(this.recordingModel.stopRecordingIfNeeded())
           .then(async function() {
             await self.performLeaveSession(deferred)
-          });
+          });*/
+          await self.performLeaveSession(deferred);
         }
       }`