Drop 3.13 incomplete backward compat in edit controller.
It is very old and broken (there is another non-backward-copmpatible
usage of `_cw_entity_fields`), better to remove it instead of fixing.
Closes #3515223.
if not rql('CWConstraintType X WHERE X name "RQLUniqueConstraint"',
ask_confirm=False):
rql('INSERT CWConstraintType X: X name "RQLUniqueConstraint"',
ask_confirm=False)