This is a C# version of: https://github.com/microsoft/BotFramework-WebChat/tree/master/samples/07.advanced-web-chat-apps/e.sso-on-behalf-of-authentication
Using a Razor Page and converted from this MVC project: https://github.com/microsoft/BotBuilder-Samples/tree/swagatm/webchatsso/experimental/sso-with-webchat/SSOBotCSharp