Add unit tests for cron job

[joeyciechanowicz]

The cron job part of the code has no testing through unit or integration tests. Integration tests don't really make sense for something that runs on a schedule, so need some unit tests around this.

There has been some issues recently with the stability of that code, so we should definitely get a bit of resliaince in our build around this.

There is currently only one unit test in the entire project 😱 .