Remove extra comment

Author: YuriiChere

ApplitoolsTutorial/UFGDemo.cs

@@ -1,7 +1,6 @@
 using Applitools;
 using Applitools.Selenium;
 using Applitools.VisualGrid;
-//using NUnit.Framework;
 using OpenQA.Selenium;
 using OpenQA.Selenium.Chrome;
 using System;