public IActionResult Index()
{
// APP SETTINGS APPROACH 1: strongly-typed IOptions<T>
var firstName = _attendee.FirstName;
// APP SETTINGS APPROACH 2: IConfiguration.GetValue
//var firstName = _configuration.GetValue<string>("AttendeeInfo:FirstName");
ViewBag.FirstName = firstName;
var sessionList = _attendeeService.GetSessions();
return(View(sessionList));
}