Update mediawiki to current Debian version

Mediawiki is now back in Debian, we should update our deployed version to it.

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Migrated from T434 (view on Phabricator)

added System administration priority:Normal labels

changed title from Update mediawiki to an upstream tarball to Update mediawiki to current Debian version

changed the description

updated description to reflect the fact that mediawiki is now back into Debian proper, including stable (!)

Upgraded to the debian package.

Ran the upgrade script for both databases:

cd /var/lib/mediawiki/maintenance
SERVER_NAME=wiki.softwareheritage.org php5 update.php
SERVER_NAME=intranet.softwareheritage.org php5 update.php

Added loading the skins to the localsettings.php

Still need to check the updated config.

added state:wip label

Checked the config, notably the plugins, to ensure that functionality was still correct. Debian doesn't provide packaged extra extensions anymore, but the ones we were using have been merged to core.

removed state:wip label

closed

mentioned in issue #761 (closed)