Update django-compressor to 2.2

[pyup-bot]

There's a new version of django-compressor available.
You are currently using 2.1.1. I have updated it to 2.2

These links might come in handy: PyPI | Changelog | Repo | Docs

Changelog

2.2

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Full Changelog <https://github.com/django-compressor/django-compressor/compare/2.1.1...2.2>_

• Switch from MD5 to SHA256 for hashes generation.

• Add Django 1.11 compatibility

• Various compatibility fixes for Python 3.6 and Django 1.8

• Made OfflineGenerationError easier to debug

• Drop support for Python 3.2

• Add new CssRelativeFilter which works like CssAbsoluteFilter but outputs relative URLs.

• Fix URL CssAbsoluteFilter URL detection

Got merge conflicts? Close this PR and delete the branch. I'll create a new PR for you.

Happy merging! 🤖