In the future need to be in a state where we can upgrade much more easily and regularly, but for now we stick to the usual upgrade path. This only concerns bumping 1 version, 1.39 is out of scope for this ticket.
Helpful links:
- https://www.mediawiki.org/wiki/MediaWiki_1.38
- https://phabricator.wikimedia.org/T295583
- https://github.com/wbstack/api/tree/main/database/mw
AC:
- For this upgrade, we disregard Fedeprops (remains disabled)
- MediaWiki version is upgraded to 1.38 for all wiki's on cloud
- Make sure the process is properly documented for future upgrades