Order alphabetically Cohorts

[diana-villalvazo-wgu]

As part of the acceptance criteria on openedx/frontend-app-instruct#52 bullet 2.
Response of this endpoint should be ordered alphabetically by name http://local.openedx.io:8000/api/cohorts/v1/courses/{course_id}/cohorts/

Note: Check if we can modify this endpoint or should we create a v2 version.