Update mini-css-extract-plugin requirement from ^0.5.0 to ^0.6.0

Updates the requirements on [mini-css-extract-plugin](https://github.com/webpack-contrib/mini-css-extract-plugin) to permit the latest version.
- [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/v0.5.0...v0.6.0)

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

package.json

@@ -67,7 +67,7 @@
 		"file-loader": "^3.0.1",
 		"jest": "^24.0.0",
 		"jest-serializer-vue": "^2.0.2",
-		"mini-css-extract-plugin": "^0.5.0",
+		"mini-css-extract-plugin": "^0.6.0",
 		"node-sass": "^4.10.0",
 		"prettier-eslint": "^8.8.2",
 		"raw-loader": "^2.0.0",