[Chore]: MST-823 Improve unit tests that covers the (#852)
[Chore]: MST-823 Improve unit tests that covers the (#852)

is_status_acknowledged functionality that exposes exam content after
exam past due, which on edx xblocks, the past due date would prevent
submission of the problems again.
edx/edx-proctoring,edx/edx-proctoring,edx/edx-proctoring