Bump mini-css-extract-plugin from 1.6.2 to 2.0.0

Bumps [mini-css-extract-plugin](https://github.com/webpack-contrib/mini-css-extract-plugin) from 1.6.2 to 2.0.0.
- [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](webpack-contrib/mini-css-extract-plugin@v1.6.2...v2.0.0)

---
updated-dependencies:
- dependency-name: mini-css-extract-plugin
  dependency-type: direct:development
  update-type: version-update:semver-major
...

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

package.json

@@ -87,7 +87,7 @@
     "markdown-spellcheck": "^1.3.1",
     "markdownlint": "^0.23.1",
     "markdownlint-cli": "^0.27.1",
-    "mini-css-extract-plugin": "^1.6.2",
+    "mini-css-extract-plugin": "^2.0.0",
     "npm-run-all": "4.1.5",
     "path-browserify": "^1.0.1",
     "prettier": "^2.3.1",