IOC tests: Parallelise with docker containers

As a developer I would like the IOC tests to run in docker containers per IOC. This means we could run several IOC tests at the same time and concatenate the output of the tests. This should hopefully speed them up when running on dev machines and the build server although it will likely be much more resource heavy.

Looks like we might be able to use something like this with `docker-compose` to create windows containers to run the IOC and emulators in: https://hub.docker.com/_/microsoft-windows-base-os-images

Docker can isolate the containers from any network interaction so there should be less chance of any interference with the host machine's network.