Bugfix: when namespace destruction causes a database error, return the

error, not nil.

namespaces.go

@@ -59,7 +59,7 @@ func (h *Headscale) DestroyNamespace(name string) error {
 	}
 
 	if result := h.db.Unscoped().Delete(&n); result.Error != nil {
-		return err
+		return result.Error
 	}
 
 	return nil