cubicweb-brainomics #3493388 Update random importer [validation pending]

Random importer should be updated using the new genetics entities.

prioritynormal
typebug
done in0.7.1
load0.100
load left0.000
closed by#f907e89018c3 [importer] Update random importer with new genetics entities, closes #3493388
patch[importer] Update random importer with new genetics entities, closes #3493388 [applied]