When I finally figure out what was wrong, I always feel really stupid. It appears, as often is the case, the solution was really simple once I knew what the problem actually was.
Fighting a CI pipeline that didn't provide any useful feedback, and that I wasn't able to replicate locally made the whole experience rather frustrating.
But in the end — after probing it repeatedly with slightly different configurations, and sneaky ways to try to get any useful logs out of it — the problem was of course on my end.
Don't include the
idcolumn when preloading test data into the database.
Can't remember why I included the id column in the first place, but it caused me much pondering. Even stranger was that it worked perfectly fine in my local dev/test setup.
At least the CI setup has become a lot more robust, and I've added a lot more logging to the test runs, so it should hopefully be easier to track down next time something mysteriously doesn't work.