Update django-environ requirement from <0.5,>=0.4 to >=0.4,<0.6
Update django-environ requirement from <0.5,>=0.4 to >=0.4,<0.6

Updates the requirements on [django-environ](https://github.com/joke2k/django-environ) to permit the latest version.
- [Release notes](https://github.com/joke2k/django-environ/releases)
- [Changelog](https://github.com/joke2k/django-environ/blob/main/CHANGELOG.rst)
- [Commits](https://github.com/joke2k/django-environ/compare/v0.4...v0.5.0)

---
updated-dependencies:
- dependency-name: django-environ
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <5bdcd3c0d4d24ae3e71b3b452a024c6324c7e4bb@github.com>
django-oscar/django-oscar,solarissmoke/django-oscar,solarissmoke/django-oscar,django-oscar/django-oscar,django-oscar/django-oscar,solarissmoke/django-oscar,solarissmoke/django-oscar,django-oscar/django-oscar