Bump mini-css-extract-plugin from 1.6.2 to 2.6.1

Bumps [mini-css-extract-plugin](https://github.com/webpack-contrib/mini-css-extract-plugin) from 1.6.2 to 2.6.1.
- [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/mini-css-extract-plugin@v1.6.2...v2.6.1)

---
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>

Author: dependabot[bot]

package.json

@@ -93,7 +93,7 @@
     "karma-jasmine": "^5.1.0",
     "karma-sonarqube-unit-reporter": "0.0.23",
     "karma-teamcity-reporter": "^1.1.0",
-    "mini-css-extract-plugin": "^1.1.0",
+    "mini-css-extract-plugin": "^2.6.1",
     "mock-socket": "^9.0.3",
     "nightwatch": "^1.4.3",
     "open": "^8.4.0",