Update dependency pinning

[sco1]

This PR updates some of our dependency pinning

• flake8-annotations v1.1 was recently released, which includes a fix for incorrect parsing of nested functions. No additional linting necessary.
• flake8-bandit has been unpinned from v1.0.2 & brought back up to current. The issue that forced the earlier downgrade has been resolved upstream in bandit.

I'm leaving this as a draft so #218 can be addressed in this PR as well. Can folks more knowledgable than I please take a look at the current package pinning and let me know what should be refined?

For reference:

django = "~=2.2"
django-crispy-forms = "~=1.7.2"
django-environ = "~=0.4.5"
django-filter = "~=2.1.0"
django-hosts = "~=3.0"
djangorestframework = "~=3.9.2"
djangorestframework-bulk = "~=0.2.1"
psycopg2-binary = "~=2.8"
django-simple-bulma = ">=1.1.7,<2.0"
django-crispy-bulma = ">=0.1.2,<2.0"
whitenoise = "==4.1.2"
requests = "~=2.21"
pygments = "~=2.3.1"
#wiki = {git = "https://github.com/python-discord/django-wiki.git"}
wiki = {path = "./docker/app/wheels/wiki-0.5.dev20190420204942-py3-none-any.whl"}
pyyaml = "*"

[lemonsaurus]

let's pin django to ~=2.2.0 then.

[sco1]

Closing to change source branch