[Authentication] Use OpenIddict Client instead of IdentityModel

[xperiandri]

What would you like to be added:

IdentityModel is a petty primitive library.
Contrary OpenIddict Client is a secure sophisticated library that covers all the possible scenarios (except WASM)

Why is this needed:

Allows to easily perform authentication setup including usage of DI

For which Platform:

• iOS
• Android
• Windows
• macOS
• Linux

[nickrandolph]

Happy to consider this as an alternative - the Authentication model is open enough that it should be easy enough to add OpenIddict Client

[xperiandri]

@jeromelaban @nick_randolph I succeeded with use of OpenIddict Client (on WinUI for now)
https://github.com/xperiandri/openiddict-core/tree/uno
So I propose to Freeze Uno.Extensions.Authentication.OIDC and invest in it instead.
As Uno.Extensions.Authentication.OIDC is very closed and inextensible contrary to OpenIddict Client.
Step left or right from the sample and you cannot do anything custom with Uno.Extensions.Authentication.OIDC

[nickrandolph]

For now this has been moved to a discussion. Rather than bulk out Uno.Extensions Authentication with more providers, I'd suggest adding a sample to uno.samples repository on how OpenIddict Client can be used