Remove unused dependency node-dir

[trivikr]

Is your feature request related to a problem? Please describe.

I noticed that node-dir dependency was added in #24

It was removed from the source code in #92 while refactoring dir.files, but it was not removed from package.json dependencies.

A search on source code does not show the dependency being used https://github.com/search?q=repo%3Afacebook%2Fjscodeshift%20node-dir&type=code

Describe the solution you'd like

Remove unused dependency node-dir

Additional context

Cleaning up, just like in 89211fa