Update linting config
Summary: The missing entries for landing were breaking ESLint and probably wasting a lot of time in Prettier. While investigating, I also noticed some other issues.
Test Plan:
- Run eslint . in the root folder
- Run prettier --write . in the root folder
- Edit a file with each possible extension and make sure it gets linted correctly and without error
Reviewers: atul
Reviewed By: atul
Subscribers: KatPo, palys-swm, Adrian
Differential Revision: https://phabricator.ashoat.com/D988