no need for attributes on legacy

Author: remicollet

build/gen_stub.php

@@ -1436,6 +1436,7 @@ public function discardInfoForOldPhpVersions(): void {
         foreach ($this->args as $arg) {
             $arg->type = null;
             $arg->defaultValue = null;
+            $arg->attributes = [];
         }
     }