[repository] forbid usage of set_attributes() in before_add_entity
set_attributes() will generate a RQL query that will silently fail.
An explicit error is better.
You can still use the ``entity[attr] = value`` notation that
won't generate a SQL query but still update the inner state
of the entity and its edited_attributes attribute.
add_relation_type('prefered_form')
rql('SET X prefered_form Y WHERE Y canonical TRUE, X identical_to Y')
commit()
drop_attribute('EmailAddress', 'canonical')
drop_relation_definition('EmailAddress', 'identical_to', 'EmailAddress')
if 'see_also' in schema:
sync_schema_props_perms('see_also', syncprops=False, syncrdefs=False)