Add the "legacy" option to "Duplicate Entries Policy" field

Currently, the "Duplicate Entries Policy" field in the User/Group directories definition only exposes 3 options :

• Studio wins = "update_duplicate" for dataLoadingPolicy field
• Instance wins = "skip_duplicate" for dataLoadingPolicy field
• Throw an error = "reject_duplicate" for dataLoadingPolicy field

It's missing at least the value "legacy" which is required not to update the directories (it could use the label "Default" in Studio).

There is another policy named "never_load" but maybe this one conflicts with the create table policy "Never". Adding it would have the advantage to expose all the existing options in Studio and advanced users will know how to set the field correctly if they need.