Adds stars to previous courses on the courses page

fixes CNVS-16717

Test Plan:
	- Go to a course and favorite it.
	- Make the course end date / term in the past.
	- You should now be able to unfavorite it, but not re-favorite it.

Change-Id: Ie289ba1c51f9d62984c4f1a87cb2021094ca29a8
Reviewed-on: https://gerrit.instructure.com/43978
Tested-by: Jenkins <jenkins@instructure.com>
Product-Review: Hilary Scharton <hilary@instructure.com>
Reviewed-by: Dan Minkevitch <dan@instructure.com>
QA-Review: Steven Shepherd <sshepherd@instructure.com>
QA-Review: Jahnavi Yetukuri <jyetukuri@instructure.com>