Update django to 2.2.7

[pyup-bot]

This PR updates django from 2.2.5 to 2.2.7.

Changelog

### 2.2.7 ``` ========================== *November 4, 2019* Django 2.2.7 fixes several bugs in 2.2.6. 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`). * Prevented :option:`migrate --plan` from showing that ``RunPython`` operations are irreversible when ``reverse_code`` callables don't have docstrings or when showing a forward migration plan (:ticket:`30870`). * Fixed migrations crash on PostgreSQL when adding an :class:`~django.db.models.Index` with fields ordering and :attr:`~.Index.opclasses` (:ticket:`30903`). * Restored the ability to override :meth:`~django.db.models.Model.get_FOO_display` (:ticket:`30931`). ========================== ``` ### 2.2.6 ``` ========================== *October 1, 2019* Django 2.2.6 fixes several bugs in 2.2.5. Bugfixes ======== * Fixed migrations crash on SQLite when altering a model containing partial indexes (:ticket:`30754`). * Fixed a regression in Django 2.2.4 that caused a crash when filtering with a ``Subquery()`` annotation of a queryset containing :class:`~django.contrib.postgres.fields.JSONField` or :class:`~django.contrib.postgres.fields.HStoreField` (:ticket:`30769`). ========================== ```

Links

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

[coveralls]

Pull Request Test Coverage Report for Build 1231

• 0 of 0 changed or added relevant lines in 0 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage remained the same at 99.275%

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Totals
Change from base Build 1198:	0.0%
Covered Lines:	2191
Relevant Lines:	2207

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💛 - Coveralls

[pyup-bot]

Closing this in favor of #297