Auth: Case insensitive ids duplicate usagestats (#50724)

* WIP

* update for prometheus

* usagestats: tests pass for user duplicate entries

* metrics: added duplicate user entries

* usagestats: adds metrics gauge for duplicate users

* usagestats: skip test for mysql

* sql in oneplace

* only use prometheus register to not panic

* usagestats: RegisterMetricsFunc with loginstats

* fix: remove unused commited code

* refactor: move test to authinfoservice

* Update pkg/models/stats.go

Co-authored-by: Emil Tullstedt <emil.tullstedt@grafana.com>

* removed prometheus metrics, due to sql cpu requirement

* Added: has_duplicate_user_entries and fix tests

* remove unused test

* fix: empty else statement removal

* missing argument to authinfoservice

Co-authored-by: Emil Tullstedt <emil.tullstedt@grafana.com>

pkg/api/user_test.go

@@ -14,6 +14,7 @@ import (
 
 	"github.com/grafana/grafana/pkg/api/dtos"
 	"github.com/grafana/grafana/pkg/components/simplejson"
+	"github.com/grafana/grafana/pkg/infra/usagestats"
 	"github.com/grafana/grafana/pkg/models"
 	acmock "github.com/grafana/grafana/pkg/services/accesscontrol/mock"
 	"github.com/grafana/grafana/pkg/services/login/authinfoservice"
@@ -48,7 +49,11 @@ func TestUserAPIEndpoint_userLoggedIn(t *testing.T) {
 		fakeNow := time.Date(2019, 2, 11, 17, 30, 40, 0, time.UTC)
 		secretsService := secretsManager.SetupTestService(t, database.ProvideSecretsStore(sqlStore))
 		authInfoStore := authinfostore.ProvideAuthInfoStore(sqlStore, secretsService)
-		srv := authinfoservice.ProvideAuthInfoService(&authinfoservice.OSSUserProtectionImpl{}, authInfoStore)
+		srv := authinfoservice.ProvideAuthInfoService(
+			&authinfoservice.OSSUserProtectionImpl{},
+			authInfoStore,
+			&usagestats.UsageStatsMock{},
+		)
 		hs.authInfoService = srv
 
 		createUserCmd := models.CreateUserCommand{