Update django-environ to 0.8.0

[pyup-bot]

This PR updates django-environ from 0.4.5 to 0.8.0.

Changelog

0.8.0

------------------------------
Added
+++++
- Log invalid lines when parse .env file
`283 <https://github.com/joke2k/django-environ/pull/283>`_.
- Added docker-style file variable support
`189 <https://github.com/joke2k/django-environ/issues/189>`_.
- Added option to override existing variables with ``read_env``
`103 <https://github.com/joke2k/django-environ/issues/103>`_,
`249 <https://github.com/joke2k/django-environ/issues/249>`_.
- Added support for empty var with None default value
`209 <https://github.com/joke2k/django-environ/issues/209>`_.
- Added ``pymemcache`` cache backend for Django 3.2+
`335 <https://github.com/joke2k/django-environ/pull/335>`_.


Fixed
+++++
- Keep newline/tab escapes in quoted strings
`296 <https://github.com/joke2k/django-environ/pull/296>`_.
- Handle escaped dollar sign in values
`271 <https://github.com/joke2k/django-environ/issues/271>`_.
- Fixed incorrect parsing of ``DATABASES_URL`` for Google Cloud MySQL
`294 <https://github.com/joke2k/django-environ/issues/294>`_.

0.7.0

------------------------------
Added
+++++
- Added support for negative float strings
`160 <https://github.com/joke2k/django-environ/issues/160>`_.
- Added Elasticsearch5 to search scheme
`297 <https://github.com/joke2k/django-environ/pull/297>`_.
- Added Elasticsearch7 to search scheme
`314 <https://github.com/joke2k/django-environ/issues/314>`_.
- Added the ability to use ``bytes`` or ``str`` as a default value for ``Env.bytes()``.

Fixed
+++++
- Fixed links in the documentation.
- Use default option in ``Env.bytes()``
`206 <https://github.com/joke2k/django-environ/pull/206>`_.
- Safely evaluate a string containing an invalid Python literal
`200 <https://github.com/joke2k/django-environ/issues/200>`_.

Changed
+++++++
- Added 'Funding' and 'Say Thanks!' project urls on pypi.
- Stop raising ``UserWarning`` if ``.env`` file isn't found. Log a message with
``INFO`` log level instead `243 <https://github.com/joke2k/django-environ/issues/243>`_.

0.6.0

----------------------------
Added
+++++
- Python 3.9, 3.10 and pypy 3.7 are now supported.
- Django 3.1 and 3.2 are now supported.
- Added missed classifiers to ``setup.py``.
- Accept Python 3.6 path-like objects for ``read_env``
`106 <https://github.com/joke2k/django-environ/issues/106>`_,
`286 <https://github.com/joke2k/django-environ/issues/286>`_.

Fixed
+++++
- Fixed various code linting errors.
- Fixed typos in the documentation.
- Added missed files to the package contents.
- Fixed ``db_url_config`` to work the same for all postgres-like schemes
`264 <https://github.com/joke2k/django-environ/issues/264>`_,
`268 <https://github.com/joke2k/django-environ/issues/268>`_.

Changed
+++++++
- Refactor tests to use pytest and follow DRY.
- Moved CI to GitHub Actions.
- Restructuring of project documentation.
- Build and test package documentation as a part of CI pipeline.
- Build and test package distribution as a part of CI pipeline.
- Check ``MANIFEST.in`` in a source package for completeness as a part of CI
pipeline.
- Added ``pytest`` and ``coverage[toml]`` to setuptools' ``extras_require``.

0.5.0

--------------------------
Added
+++++
- Support for Django 2.1 & 2.2.
- Added tox.ini targets.
- Added secure redis backend URLs via ``rediss://``.
- Add ``cast=str`` to ``str()`` method.

Fixed
+++++
- Fixed misspelling in the documentation.

Changed
+++++++
- Validate empty cache url and invalid cache schema.
- Set ``long_description_content_type`` in setup.
- Improved Django 1.11 database configuration support.

Links

• PyPI: https://pypi.org/project/django-environ
• Changelog: https://pyup.io/changelogs/django-environ/
• Docs: https://django-environ.readthedocs.org

[pyup-bot]

Closing this in favor of #441