fs: fix typo in mkdir example

PR-URL: #44791
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Antoine du Hamel <duhamelantoine1995@gmail.com>
Reviewed-By: Michaël Zasso <targos@protonmail.com>
Reviewed-By: Akhil Marsonya <akhil.marsonya27@gmail.com>

doc/api/fs.md

@@ -1058,7 +1058,7 @@ import { mkdir } from 'node:fs/promises';
 
 try {
   const projectFolder = new URL('./test/project/', import.meta.url);
-  const createDir = await mkdir(path, { recursive: true });
+  const createDir = await mkdir(projectFolder, { recursive: true });
 
   console.log(`created ${createDir}`);
 } catch (err) {