chore(deps-dev): bump mini-css-extract-plugin from 1.5.1 to 1.6.0

Bumps [mini-css-extract-plugin](https://github.com/webpack-contrib/mini-css-extract-plugin) from 1.5.1 to 1.6.0.
- [Release notes](https://github.com/webpack-contrib/mini-css-extract-plugin/releases)
- [Changelog](https://github.com/webpack-contrib/mini-css-extract-plugin/blob/master/CHANGELOG.md)
- [Commits](https://github.com/webpack-contrib/mini-css-extract-plugin/compare/v1.5.1...v1.6.0)

Signed-off-by: dependabot[bot] <support@github.com>

package.json

@@ -148,7 +148,7 @@
     "license-checker": "^25.0.0",
     "lint-staged": "=10.5.4",
     "local-web-server": "^4.2.1",
-    "mini-css-extract-plugin": "^1.5.1",
+    "mini-css-extract-plugin": "^1.6.0",
     "mocha": "=8.3.2",
     "nightwatch": "^1.6.3",
     "node-sass": "^4.14.1",