Bump to Django 3 and only list what is needed.

requirements.txt

@@ -1,35 +1,11 @@
-cached-property==1.5.1
-certifi==2019.11.28
-chardet==3.0.4
-coreapi==2.3.3
-coreschema==0.0.4
-Django==2.2.8
+Django==3.0.2
+djangorestframework==3.11.0
 django-auth-ldap==2.1.0
 django-logging-json==1.15
 django-netfields==1.2.2
 django-rest-swagger==2.2.0
 django-url-filter==0.3.14
-djangorestframework==3.10.3
-drf-extensions==0.5.0
-elasticsearch==7.1.0
-enum-compat==0.0.3
 gunicorn==20.0.4
 idna==2.8
-itypes==1.1.0
-Jinja2==2.10.3
-MarkupSafe==1.1.1
-netaddr==0.7.19
-openapi-codec==1.3.2
-pip-autoremove==0.9.1
 psycopg2-binary==2.8.4
-pyasn1==0.4.8
-pyasn1-modules==0.2.7
-python-ldap==3.2.0
-pytz==2019.3
-requests==2.22.0
-sentry-sdk==0.13.4
-simplejson==3.17.0
-six==1.13.0
-sqlparse==0.3.0
-uritemplate==3.0.0
-urllib3==1.25.7
+sentry-sdk==0.14.0