test: do not spawn rmdir in test-statwatcher

PR-URL: #28276
Refs: #21425
Reviewed-By: Rich Trott <rtrott@gmail.com>
Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: Franziska Hinkelmann <franziska.hinkelmann@gmail.com>

test/async-hooks/test-statwatcher.js

@@ -11,7 +11,7 @@ const path = require('path');
 if (!common.isMainThread)
   common.skip('Worker bootstrapping works differently -> different async IDs');
 
-tmpdir.refresh();
+tmpdir.refresh({ spawn: false });
 
 const file1 = path.join(tmpdir.path, 'file1');
 const file2 = path.join(tmpdir.path, 'file2');