我自己找到了解决方案

//Save JSON file on my Drive  
  let fileSets = {
    title: 'JSON_Test.json',
    mimeType: 'application/json'
  };
  let blob = Utilities.newBlob(JSON.stringify(arr[0]), "application/vnd.google-apps.script+json"); //modified
  Drive.Files.insert(fileSets, blob);