Update clean-css-cli to the latest version 🚀

[greenkeeper]

Version 4.0.6 of clean-css-cli just got published.

Dependency	clean-css-cli
Current Version	4.0.5
Type	devDependency

The version 4.0.6 is not covered by your current version range.

Without accepting this pull request your project will work just like it did before. There might be a bunch of new features, fixes and perf improvements that the maintainers worked on for you though.

I recommend you look into these changes and try to get onto the latest version of clean-css-cli.
Given that you have a decent test suite, a passing build is a strong indicator that you can take advantage of these changes by merging the proposed change into your project. Otherwise this branch is a great starting point for you to work on the update.

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Commits

The new version differs by 2 commits .

• b79a554 Version 4.0.6.
• 1b9fa20 Bumps clean-css dependency to 4.0.6.

See the full diff.

Not sure how things should work exactly?

There is a collection of frequently asked questions and of course you may always ask my humans.

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Your Greenkeeper Bot 🌴

[CLAassistant]

Thank you for your submission, we really appreciate it. Like many open source projects, we ask that you sign our Contributor License Agreement before we can accept your contribution.