Chore: Remove bus.Bus field (#47695) (#47704)

* Chore: Remove bus.Bus field

* fix integration test

(cherry picked from commit e86b6662a1)

Co-authored-by: Serge Zaitsev <serge.zaitsev@grafana.com>

pkg/tests/api/alerting/api_admin_configuration_test.go

@@ -12,7 +12,6 @@ import (
 	"github.com/prometheus/common/model"
 	"github.com/stretchr/testify/require"
 
-	"github.com/grafana/grafana/pkg/bus"
 	"github.com/grafana/grafana/pkg/infra/tracing"
 	"github.com/grafana/grafana/pkg/models"
 	apimodels "github.com/grafana/grafana/pkg/services/ngalert/api/tooling/definitions"
@@ -35,8 +34,6 @@ func TestAdminConfiguration_SendingToExternalAlertmanagers(t *testing.T) {
 	})
 
 	grafanaListedAddr, s := testinfra.StartGrafana(t, dir, path)
-	// override bus to get the GetSignedInUserQuery handler
-	s.Bus = bus.GetBus()
 
 	// Create a user to make authenticated requests
 	userID := createUser(t, s, models.CreateUserCommand{