Ares LTI is inconsistent about setting user's types to Instructor.
When an existing user comes into Ares through LTI with the role of Instructor, their Ares user type will be set to Instructor only if Ares needs to create the course. If the course already exists, they will be assigned as the instructor but their Ares user type can remain as User.
Rather than make this so that the user is never set to instructor or always set to instructor, we want to correct this by changing how the instructor can be selected/changed in the staff client. This would also tie into the option to have multiple full instructors down the road.
If it's creating the course, it sets that user as the instructor for the course *and* makes that user an Instructor usertype. If the course already exists, it add them to the course but doesn't change their usertype.