Enforcement: Date Extensions tab #491

Permissions

• courses.view_learner_extensions
• courses.manage_learner_extensions

Endpoints

• UnitExtensionsView and GradedSubsectionsView → view_learner_extensions
• ChangeDueDateView → manage_learner_extensions

Acceptance criteria

• The common criteria from Backend permission enforcement (LMS) #485 are met.

Blocked by: #486