In {T220235} it was decided to use plain Docker VMs for services that run on the production Kubernetes cluster. Given that the core MediaWiki application is moving to Kubernetes in the future (#mw-on-k8s) and we have more and more services that MediaWiki depends on I believe it's a good idea to at least revisit that decision.
Beta cluster currently runs some services in Docker containers dedicated VMs (`deployment-docker-*`) and a few in the legacy `deployment-sca[01-02]` cluster running Jessie and with Puppet totally broken due to production setup changes. New services are deployed and existing ones updated rarely if at all.
Resource and implementation wide I am unfortunately not sure how feasible this is. The project is almost out of Cloud VPS quota (T257118) plus setting up and maintaining a Kubernetes cluster and services running in it requires a considerable amount of time which I'm not sure who would put it into this project.