Update dependencies for security vulnerabilities

[bear]

pipfile.lock and requirements.txt need the following change applied: django>=2.0.8

CVE-2018-14574 moderate severity Vulnerable versions: >= 2.0, < 2.0.8 Patched version: 2.0.8 django.middleware.common.CommonMiddleware in Django 1.11.x before 1.11.15 and 2.0.x before 2.0.8 has an Open Redirect.

CVE-2018-6188 moderate severity Vulnerable versions: >= 2.0.0, < 2.0.2 Patched version: 2.0.2 django.contrib.auth.forms.AuthenticationForm in Django 2.0 before 2.0.2, and 1.11.8 and 1.11.9, allows remote attackers to obtain potentially sensitive information by leveraging data exposure from the confirm_login_allowed() method, as demonstrated by discovering whether a user account is inactive.