[is.js](https://github.com/node-oauth/node-oauth2-server/blob/master/lib/validator/is.js) really slows down the tests. What do you guys think about moving it to it's own repository and adding it as a dependency? <img width="1028" alt="Screen Shot 2021-11-10 at 8 42 09 AM" src="https://user-images.githubusercontent.com/747587/141144881-cc8d6604-e235-40e0-b8f2-ce9ce37f0435.png">