Create Django version of eduNEXT Flask codejail service

[robrap]

Acceptance Criteria:

• Review and complete setup of new repo.
  • See [GH Request] Create openedx/codejail-service repo openedx/axim-engineering#1353 (comment)
• Django based version of eduNEXT flask codejail service up and running (happy path) in devstack.

PRs:

• Skeleton that runs in devstack and doesn't do anything:
  • Dockerfile: feat: Add codejail service public-dockerfiles#85
  • Application: Initialize codejail_service application openedx/codejail-service#2
  • Devstack: feat: Add codejail service devstack#102
• Version that can actually respond to codejail requests

Implementation notes:

• This will probably be a fairly straightforward combination of:
  • Cookiecutter django-ida
  • Existing POC in edx-arch-experiments codejail-service app but remove the OAuth parts (won't be using service-to-service auth here)
  • Whatever we're doing in edx/public-dockerfiles
• Only needs the happy path worked out for now, since we have a testing ticket that will explore the various sad paths.
• New repo was requested of Axim here: [GH Request] Create openedx/codejail-service repo openedx/axim-engineering#1353
• This should be generously timeboxed. We do want a Django version, but we also want to know if we hit any major snags.
• We should be able to configure use of this service in both Studio and LMS using existing config (e.g. however the Flask service is configured).
• The API of the service (e.g. LMS => codejail calls) should go unchanged.
• Codejail will be a separate devstack docker container.