Additional changes:
* Dropped .inc files from .phpcs.xml (T200956).
* Added the `wikimedia/mediawiki` profile in .eslintrc.json (T262222).
* Added the `wikimedia/jquery` profile in .eslintrc.json (T262222).
* Removed global `$`, included in the `wikimedia/jquery` profile (T262222).
* Removed global `mw`, included via `wikimedia/mediawiki` profile (T262222).
* Dropped the emtpy global definition in .eslintrc.json.
Change-Id: I58295f83ff82849aaef84934662911a69e272e2a