Introduce IdentityUserIntegrationService

[hikalkan]

IUserRoleFinder is used by RolePermissionManagementProvider to get a list of role names of a user to be able to manage the user's permissions.

The remote implementation of the IUserRoleFinder interface is HttpClientUserRoleFinder which was using IIdentityUserAppService.GetRolesAsync method. IIdentityUserAppService is an application service and implements authorization. When you implement a microservice solution, permission management can be in one service and identity management can be in another service. In that case, the permission microservice makes an HTTP request to obtain user's roles. Since the used appservice method requires authorization, we were authenticating the permission microservice first, then authorizing it to be able to use the remote identity service.

That authentication/authorization brings additional complexity. We want to remove that, so we will use an non-authorized integration service for that reason.

This is a breaking change for microservice solutions, because of two reasons:

• That permission to identity service call is not authorized anymore. That won't break applications, but should be cared.
• Since integration services are not exposed by default, we should explicitly enable it (see how to expose it). Otherwise, the operation is failed and you get a 404 error from the identity microservice.