Update Index.cshtml

[aliozgur]

Fix for: ExceptionMessage: "Object reference not set to an instance of an object." ExceptionType: "System.NullReferenceException" Message: "An error has occurred." StackTrace: " at HawkNet.HttpRequestMessageExtensions.<AuthenticateAsync>d__7.MoveNext() ?--- End of stack trace from previous location where exception was thrown --- ? at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task) ? at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task) ? at System.Runtime.CompilerServices.TaskAwaiter1.GetResult() ? at HawkNet.WebApi.HawkMessageHandler.<SendAsync>d__0.MoveNext() ?--- End of stack trace from previous location where exception was thrown --- ? at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task) ? at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task) ? at System.Runtime.CompilerServices.TaskAwaiter1.GetResult() ? at System.Web.Http.Cors.CorsMessageHandler.<SendAsync>d__0.MoveNext() ?--- End of stack trace from previous location where exception was thrown --- ? at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task) ? at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task) ? at System.Runtime.CompilerServices.TaskAwaiter`1.GetResult() ? at System.Web.Http.HttpServer.<SendAsync>d__0.MoveNext()"