check data config matches expected sources/lift sources from config for pv_site

[AUdaltsova]

Description

Currently pv_site only takes in pv and nwp regardless of what is in the configs, and to add new source you need to go into the datamodule class and add it by hand here

Possible Implementation

I think it would be nice to either lift the sources off the config automatically or at least do a check at some point that there are no unexpected sources requested, because currently it takes quite a lot of debugging to reach this spot