Updated mediawiki/extensions
Project: mediawiki/extensions/UniversalLanguageSelector  b7e6aaa475ebac4d8b0fbbf96487f021981ec9fc

shellcheck fixes

* Script: https://github.com/koalaman/shellcheck
* Use $(..) instead of deprecated `..`
* Use double quote to prevent globbing and word splitting.

Change-Id: I68372d4e29ae34e0704e5a605447ad17bf0666d7