Analysis details below... however the test in question was written with the assumption that job run history is immediately available when a job run finishes... which is NOT true. Metronome asynchronously updates job run history and will eventually be correct. Tests need to be written with this in mind.
This is a different failure; instead of a 502 we get a 404.
Task in question did finish. Same time at which we got 404.
However, the test queried the endpoint `/service/metronome/v1/jobs/test.metronome?embed=history` at `2018-10-09 23:15:02,560` (35 milliseconds after getting a 404 for the current job). Maybe there's a race?
Conclusion: Not a Metronome issue. The job history is updated asynchronously and there's no guarantee that if you get a 404 for a job run as an indicator of completion, that this means the job history is immediately available. Test needs to be updated to use eventually.