Bump django from 3.0.7 to 3.1.12 in /requirements (#486)

* Bump django from 3.0.7 to 3.1.12 in /requirements

Bumps [django](https://github.com/django/django) from 3.0.7 to 3.1.12.
- [Release notes](https://github.com/django/django/releases)
- [Commits](django/django@3.0.7...3.1.12)

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

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

* Readme update t force Travis build.

* New commit to force travis-ci checks.

Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
Co-authored-by: Juan Pablo Menichetti <jmenichetti@evernote.com>

README.md

@@ -38,3 +38,5 @@ Copying
 Zing is released under the General Public License, version 3 or later. See the
 [LICENSE](https://github.com/evernote/zing/blob/master/LICENSE) file for
 details.
+
+Last updated: 2021-08-09

requirements/base.txt

@@ -1,4 +1,4 @@
-Django==3.0.7
+Django==3.1.12
 
 # Django apps
 django-allauth==0.41.0