Add audience to oidc provider options

[juliofuentescerrada]

Hi! Tried to set up Esquio with Auth0 and got some issues with the token validation. The application was returning a 401 Bearer error="invalid_token" response and parsing the token in jwt.io showed no payload.

Finally found out that Auth0 requires the audience to be sent during the authorization request, which can be achieved by adding it to the provider options.

References:

• Securing Blazor WebAssembly Apps
• Invalid access token payload, jwt encrypted with A256GCM

Tested the application with Auth0 and Duende demo server and everything was working just fine after the proposed change.

Thanks for the awesome work!