Course Editor receives 403 error when copy a unit to the clipboard #403

Description

Currently, a user assigned the Course Editor role can view and edit course content in Studio. However, when the user attempts to copy a unit to the clipboard, the backend returns a 403 Forbidden error, preventing the action from completing.

Expected behavior

A Course Editor should have the necessary permissions to copy a unit to the clipboard in order to duplicate or move content across the course without encountering authorization errors.

Actual behavior

The backend blocks the copy action, returning a 403 error on the clipboard API endpoint, even though the user has edit access to the course.

Steps to reproduce

1. Log in to Studio with an account that has the Course Editor role for a specific course.
2. Navigate to the course outline.
3. Locate any existing unit and click the to Copy to clipboard
4. Observe that the action fails.
5. Check the browser's network tab and observe a 403 Forbidden error being returned by the POST http://studio.local.openedx.io:8001/api/content-staging/v1/clipboard/ endpoint.