cubicweb #4067694 Drop the reference to the 'source' column in dataimport [validation pending]

prioritynormal
typetask
done in3.19.2
load0.200
load left0.000
closed by#c7ce035aede8 [dataimport] Drop reference to the 'source' column (closes #4067694).
patch[dataimport] Drop reference to the 'source' column (closes #4067694). [applied]