Update postcss-cli to the latest version 🚀

The devDependency postcss-cli was updated from `6.1.3` to `7.0.0`.

This version is not covered by your current version range.

If you don’t accept this pull request, your project will work just like it did before. However, you might be missing out on a bunch of new features, fixes and/or performance improvements from the dependency update.

Publisher: ryanzim License: MIT

Release Notes for 7.0.0 / 2020-01-07

BREAKING: Drop support for Node 6 & 8
Update globby, which may be a breaking change for a small number of users using certain glob patterns, see https://github.com/mrmlnc/fast-glob#pattern-syntax for details (#303)
Update dependencies

Commits

The new version differs by 15 commits.

745ad2c 7.0.0
cf6ea09 Update eslint config
ea1cec4 Update eslint-config-problems to version 3.1.0 (#306)
1519430 Update globby to version 10.0.1 (#303)
5b47456 Update eslint to version 6.8.0 (#305)
e241672 Update nyc to version 15.0.0 (#297)
4a87ff1 Update chalk to version 3.0.0 (#294)
e666505 Update prettier to version 1.19.1 (#304)
0d3591a Update ava to version 2.4.0 (#302)
cb9f451 Update fs-extra to version 8.1.0 (#301)
4f68a46 Update chokidar to version 3.3.0 (#300)
5c22ddb Update yargs to version 15.0.2 (#298)
79eb0ac Update get-stdin to version 7.0.0 (#273)
71384c6 Update Travis config; remove AppVeyor
6b92df3 BREAKING: Drop Node 6 & 8; test on new Node versions

See the full diff

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cdunnnnnnn / rhubarb