Update django to 1.11.26

[pyup-bot]

This PR updates Django from 1.11.25 to 1.11.26.

Changelog

1.11.26

============================

*November 4, 2019*

Django 1.11.26 fixes a regression in 1.11.25.

Bugfixes
========

* Fixed a crash when using a ``contains``, ``contained_by``, ``has_key``,
``has_keys``, or ``has_any_keys`` lookup on
:class:`~django.contrib.postgres.fields.JSONField`, if the right or left hand
side of an expression is a key transform (:ticket:`30826`).


============================

Links

• PyPI: https://pypi.org/project/django
• Changelog: https://pyup.io/changelogs/django/
• Homepage: https://www.djangoproject.com/

[coveralls]

Coverage remained the same at 92.593% when pulling 3ff9b18 on pyup-update-django-1.11.25-to-1.11.26 into efd57cc on master.