Fix `set_ids_for_new_custom_attributes`
Fix `set_ids_for_new_custom_attributes`

Set attributable_id to parent object instead of to custom
attribute value's ID (which is obj.id in the scope of the loop
after recent linting changes).

andrei-karalionak/ggrc-core,andrei-karalionak/ggrc-core,josthkko/ggrc-core,AleksNeStu/ggrc-core,selahssea/ggrc-core,j0gurt/ggrc-core,NejcZupec/ggrc-core,AleksNeStu/ggrc-core,selahssea/ggrc-core,edofic/ggrc-core,kr41/ggrc-core,VinnieJohns/ggrc-core,josthkko/ggrc-core,edofic/ggrc-core,plamut/ggrc-core,josthkko/ggrc-core,NejcZupec/ggrc-core,j0gurt/ggrc-core,josthkko/ggrc-core,AleksNeStu/ggrc-core,kr41/ggrc-core,andrei-karalionak/ggrc-core,plamut/ggrc-core,edofic/ggrc-core,kr41/ggrc-core,VinnieJohns/ggrc-core,plamut/ggrc-core,VinnieJohns/ggrc-core,selahssea/ggrc-core,VinnieJohns/ggrc-core,kr41/ggrc-core,NejcZupec/ggrc-core,plamut/ggrc-core,j0gurt/ggrc-core,NejcZupec/ggrc-core,j0gurt/ggrc-core,AleksNeStu/ggrc-core,edofic/ggrc-core,selahssea/ggrc-core,andrei-karalionak/ggrc-core