fix: bump django from 2.2.17 to 2.2.18 (#1489)

* build: bump django from 2.2.17 to 2.2.18

Bumps [django](https://github.com/django/django) from 2.2.17 to 2.2.18.
- [Release notes](https://github.com/django/django/releases)
- [Commits](django/django@2.2.17...2.2.18)

Signed-off-by: dependabot[bot] <support@github.com>

* build: bump django from 2.2.17 to 2.2.18

Bumps [django](https://github.com/django/django) from 2.2.17 to 2.2.18.
- [Release notes](https://github.com/django/django/releases)
- [Commits](django/django@2.2.17...2.2.18)

Signed-off-by: dependabot[bot] <support@github.com>

* Merge branch 'development' into dependabot/pip/django-2.2.18

* Merge branch 'dependabot/pip/django-2.2.18' of https://github.com/ocadotechnology/aimmo into dependabot/pip/django-2.2.18

* update Pipfile.lock