Ensure we generate and use dedicated serving data

[seberg]

I just realized that my old output folder with data has a serving and training folder. I suspect we need to generate data for both serving and training and I think we currently do not have a step for creating it (or use it).

CC @csadorf I suspect this is simple and relatively low prio, because it is easy to fix things up if we want it.

[csadorf]

Yes, you are correct that we should split training and serving data. I kind of intentionally "forgot" about that to not overcomplicate things in that first iteration, but we can quickly add that. I'll take care of that.

[seberg]

ooops, sorry wrong repo, had this randomly open!