Correct http status code set

Author: i4004

src/SampleApps/SampleApp.SelfHosted/Controllers/HttpErrors/Http404Controller.cs

@@ -9,7 +9,7 @@ public class Http404Controller : Controller
 	{
 		public override ControllerResponse Invoke()
 		{
-			return new StaticTpl("HttpErrors/Http404", StringTable.PageTitle404);
+			return new StaticTpl("HttpErrors/Http404", StringTable.PageTitle404, 404);
 		}
 	}
 }