## Problem
Our dockerfiles, for some historical reason, have unconventional names
`Dockerfile.<something>`, and some tools (like GitHub UI) fail to highlight
the syntax in them.
> Some projects may need distinct Dockerfiles for specific purposes. A
common convention is to name these `<something>.Dockerfile`
From: https://docs.docker.com/build/concepts/dockerfile/#filename
## Summary of changes
- Rename `Dockerfile.build-tools` -> `build-tools.Dockerfile`
- Rename `compute/Dockerfile.compute-node` ->
`compute/compute-node.Dockerfile`
