Lint SQL files using php-sqllint
- Do not write 'connect' line from 'create_tables*' sql files: it breaks linting, and is not needed as we always explicitly connect to the database when using them when necessary.
- Remove the workaround in Dockerfile (as removed per above)
- Add cweiske/php-sqllint to composer.json
- Add secure-http config option (otherwise install fails)
Bug: T132641
Change-Id: I9e4bb96d9ddb2f090e704df3207b4c5f01027ac8