Move the monitor into a container

[leighmcculloch]

Most of the elements of this integration test suite run inside containers, except the monitor and ngrok. This means that running these integration tests require installing applications and tools locally which makes it harder to run these locally.

We should make it really easy and predictable for anyone to quickly run these integration tests.

We can make it easier to run these tests if they are entirely contained within containers that use their own network to communicate with each other (in addition to also use ngrok internally).