Merge branch 'use-kubernetes-runner' into 'master'

Migrate to Kubernetes for tests

This will change the build_branch and lint steps to be executed on the Kubernetes cluster in Azure (see for the whole story). This is anticipated to save us significant bandwidth charges!

I've scheduled discussion of this on the Monday team call.

See merge request !4284
4 jobs for lm-update-handbook-support-security-process in 4 minutes and 35 seconds (queued for 2 seconds)