Write test automation for GItlab sync script

As we can control the full set of data for the local Gitlab instances, we can use API calls to setup test environments and validate them afterwards. We should be able to make it in such a way that its a single command that sets the test environment, runs the sync, and tests the results afterwards.

We can do this with some normal js/ts to generate the initial content using the secret used for the sync script, run the script, and use our normal testing harness with some helper methods to validate key areas within the environment.