Decouple Admin UI from EntityFramework

[tmm360]

I'm trying to implement Admin UI into a project that doesn't use EntityFramework. We are in fact using MongoDB with a custom ODM framework (https://github.com/Etherna/mongodm), but Skoruba.IdentityServer4.Admin.UI has direct dependency to a lot of EF packages, and EF types are directly involved into exposed interfaces. They shouldn't.

My propose instead is to totally decouple the Admin UI from EntityFramework, and expose configurations only with agnostic interfaces, that can be implemented with a pre-built EF package, or by custom implementations on application side.

[skoruba]

Hey @tmm360 - thank you for your tip - I would consider change it for my Duende IdentityServer Admin version.