Context
"WARN[0000] /home/novemlinguae/mediawiki/
docker-compose.yml: version is obsolete"
Fixes "WARN[0000] /home/novemlinguae/mediawiki/
docker-compose.yml: version is obsolete"
Proposal
Remove the version key in docker-compose.yml.
Consequences
Potentially older versions of Docker (pre 2022 / 4.9.1) could have issues without the version number present.