We've long rolled out the
`COURSEWARE_COURSE_NOT_STARTED_ENTERPRISE_LEARNER_ERROR` setting toggle so
it should be safe to remove.
I'm completely at a loss as to why course access checks are not
returning the `course_not_started_enterprise_learner` error code when it
should, but it does in stage/local, so this PR is grasping at straws.
ENT-8766