Code sample needs to define what the configuration object is

The code samples refer to a Configuration object but do not define what it is. Obviously it references some configuration values, but it doesn't provide any perspective on what those values should be to get ADFS to work.

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#### Document Details

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* ID: 59d6d442-8d46-3f9e-e75a-ad9d900fc117
* Version Independent ID: d07c4058-452f-cdac-c59d-8f09e70a43f3
* Content: [Authenticate users with WS-Federation in ASP.NET Core](https://docs.microsoft.com/en-us/aspnet/core/security/authentication/ws-federation?view=aspnetcore-6.0)
* Content Source: [aspnetcore/security/authentication/ws-federation.md](https://github.com/dotnet/AspNetCore.Docs/blob/main/aspnetcore/security/authentication/ws-federation.md)
* Product: **aspnet-core**
* Technology: **aspnetcore-security**
* GitHub Login: @chlowell
* Microsoft Alias: **scaddie**