Consider expanding docs for Duende.AspNetCore.Authentication.JwtBearer

[maartenba]

These are now part of the IdentityServer docs, should we have a separate section for Duende.AspNetCore.Authentication.JwtBearer to allow for easier discovery of the library?

[maartenba]

Note there are some docs at https://docs.duendesoftware.com/identityserver/apis/aspnetcore/confirmation/#validating-dpop