Feature Description

We're expecting developers to run phpcs/phpcbf manually before creating a PR. This can be automated easily via husky. Husky is also used by Gutenberg to lint before commit.

So here are things that we need to do:

1. Add a pre-commit hook via husky to run phpcbf before commit to auto-fix phpcs errors.
2. Run phpcs so that users can manually resolve any errors which are not automatically fixable.