chore: modernize repo supporting latest django-app cookiecutter changes

[mariajgrimaldi]

Description:
This PR changes:

• The main CI workflow: adding support for Django 3.2 and Django 4.2 testing environments
• tox.ini: adding the necessary configurations for multiple django versions
• Constraint files: currently, for this kind of repo constraints are read from the edx-lint repository https://github.com/openedx/edx-lint/blob/master/edx_lint/files/common_constraints.txt
• Makefile: removing unnecessary common_constraints file since it was removed in favor of the previous item, and test requirements with multiple django versions

[openedx-webhooks]

Thanks for the pull request, @mariajgrimaldi! Please note that it may take us up to several weeks or months to complete a review and merge your PR.

Feel free to add as much of the following information to the ticket as you can:

• supporting documentation
• Open edX discussion forum threads
• timeline information ("this must be merged by XX date", and why that is)
• partner information ("this is a course on edx.org")
• any other information that can help Product understand the context for the PR

All technical communication about the code itself will be done via the GitHub pull request interface. As a reminder, our process documentation is here.

Please let us know once your PR is ready for our review and all tests are green.

[openedx-webhooks]

@mariajgrimaldi 🎉 Your pull request was merged! Please take a moment to answer a two question survey so we can improve your experience in the future.