'FATAL: Role 'root' does not exist' while running regression_incremental

[benelot]

Hello!

I am currently running your tutorial on setting up NannyML in a production environment. While running the basic regression_incremental. The example seems to work and I get alerts on the grafana dashboard. But in the docker compose output, I frequently see the regression_incremental-metrics-store-1 reporting 'role "root" does not exist'. As far as I see, that could hint to a postgres problem with a non-existant root user. However, I am not sure yet what it could be. I will report more in case I find anything.