Incorrect insconf in nested observation results

[sergiopasra]

The insconf is assigned in

numina/src/numina/dal/dictdal.py

Line 194 in 1cd1a43

obsres.configuration = self.assembly_instrument(key, date_obs, keyname)

but, at that stage, the results of the reduction in the case of nested reductions are not included in the ObsResult, so the assigned insconf is wrong.