Fixes #20950 - Use 'distinct' in AR finders

Fixes #20956 - Don't pass class constants to AR conditions

fixes #20653 - ui notifications for hosts with usergroup owner

Fixes #20516 - GET hosts API displays owner_name attribute

Fixes #20622 - puppet import does not refresh all statuses

Fixes #20248, #20327 - Respect context in CSV export

Since CSV export is done using an enumerator which is executed by a
different thread to the one that creates it, we need to manually pass in
the context (user, location, organization) to the enumerator.

Fixes #20401 - Allow pxe_loader in the Jail

Fixes #20119 - Be more descriptive when validating hostname

Signed-off-by: Boaz Shuster <ripcurld.github@gmail.com>

Fixes #19826 - Fix Rails/ActiveSupportAliases cop

Fixes #19828 - Fix Rails/Blank cop

I disabled the default UnlessPresent value since sometimes it's clearer
to use `unless attribute.present?` instead of `if attribute.blank?`.