Update general courses ordering_fields attribute to allow ordering by start date

[jfaMan]

Change description

Update general courses ordering_fields attribute to allow ordering by start date.

I’m looking to add course sorting in the dashboard by course start date. Currently sorting is possible by course name (display_name) and pacing (self_paced). Current sorting options are done at the figures API level (figures/api/course-general/). Since start_date is already defined in the serializer, I believe start_date just needs to be added to the ordering_fields attribute.

Also, date_joined is in the ordering_fields attribute, but it's not defined in GeneralCourseDataSerializer and returns a 500 error in Postman. I believe this was mistakingly added from the User/Learner serializers (e.g.).

New to Python and Django though, so correct me if I'm wrong anywhere.

Type of change

• Bug fix (fixes an issue)
• New feature (adds functionality)

Related issues

Checklists

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• Application changes have been tested thoroughly
• Automated tests covering modified code pass

Security

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