Auth: Set the default org after User login (#83918)

* poc

* add logger, skip hook when user is not assigned to default org

* Add tests, move to hook folder

* docs

* Skip for OrgId < 1

* Address feedback

* Update docs/sources/setup-grafana/configure-grafana/_index.md

* lint

* Move the hook to org_sync.go

* Update pkg/services/authn/authnimpl/sync/org_sync.go

* Handle the case when GetUserOrgList returns error

---------

Co-authored-by: Christopher Moyer <35463610+chri2547@users.noreply.github.com>
Co-authored-by: Karl Persson <kalle.persson@grafana.com>

pkg/services/user/user.go

@@ -6,6 +6,7 @@ import (
 	"github.com/grafana/grafana/pkg/registry"
 )
 
+//go:generate mockery --name Service --structname MockService --outpkg usertest --filename mock.go --output ./usertest/
 type Service interface {
 	registry.ProvidesUsageStats
 	Create(context.Context, *CreateUserCommand) (*User, error)