Users authenticated via a Dropbox Business app must provide a member_id (by the Dropbox-Select-User header, for example) when making a User Endpoint request.
It's not clear how to fetch that member_id token. The best I can come up with is to go through `/members/list` until I can find an entry that matches the current user.
Is there a way of quickly finding the member_id of the authenticated user to send through for the Dropbox-Select-User header?