Post Duplicator <= 3.0.11 - Missing Authorization to Authenticated (Contributor+) Post Duplication with Arbitrary Author Attribution

The Post Duplicator plugin for WordPress is vulnerable to unauthorized modification of data due to a missing capability check on the `duplicate_post()` function in all versions up to, and including, 3.0.11. This is due to the function not verifying that the user has `edit_others_posts` capability before accepting a `selectedAuthorId` parameter via the `duplicate-post` REST endpoint. This makes it possible for authenticated attackers, with Contributor-level access and above, to create duplicated posts attributed to any user, including administrators.