SQL -> data

Changing SQL language definition back to `data`. A bunch of repos are being wildly misrepresented e.g. https://github.com/linkedin/sensei https://github.com/postgis/postgis https://github.com/TrinityCore/TrinityCore as they're storing SQL data exports in their repositories.

Until we have a better (repo-specific) ignore option such as a `.linguistignore` this needs to be reverted to `data`