Reference
- https://identityserver4.readthedocs.io/en/latest/
- https://feras.blog/how-to-use-asp-net-identity-and-identityserver4-in-your-solution/
- https://fullstackmark.com/post/21/user-authentication-and-identity-with-angular-aspnet-core-and-identityserver
- https://github.com/IdentityServer/IdentityServer4