Allow reordering sponsors and team members

[therealsujitk]

During Vibrance'23, faculties gave me hell because they wanted all faculty members and sponsors in a very specific order 🥲. It would be convenient to add a feature where team names, team members and sponsors can be reordered.

The current workaround is to prefix the team names, team members and sponsors with a number so the API returns them in ascending order of the numbers. This prefix is later trimmed off at the frontend.