Dashboard: skip deletion validation on standalone mode (#110938)

* Dashboard: skip deletion validation on standalone mode

* move dashboard check right before provisioning service is used

* use isInterfaceNil

pkg/registry/apis/dashboard/register.go

@@ -58,6 +58,7 @@ import (
 	"github.com/grafana/grafana/pkg/storage/legacysql/dualwrite"
 	"github.com/grafana/grafana/pkg/storage/unified/apistore"
 	"github.com/grafana/grafana/pkg/storage/unified/resource"
+	"github.com/grafana/grafana/pkg/util"
 )
 
 var (
@@ -279,6 +280,11 @@ func (b *DashboardsAPIBuilder) validateDelete(ctx context.Context, a admission.A
 		return fmt.Errorf("%v: %w", "failed to parse namespace", err)
 	}
 
+	// HACK: deletion validation currently doesn't work for the standalone case. So we currently skip it.
+	if b.isStandalone && util.IsInterfaceNil(b.dashboardProvisioningService) {
+		return nil
+	}
+
 	// The name of the resource is the dashboard UID
 	dashboardUID := a.GetName()