Bump less from 3.11.1 to 4.1.1 in /graylog2-web-interface

Bumps [less](https://github.com/less/less.js) from 3.11.1 to 4.1.1.
- [Release notes](https://github.com/less/less.js/releases)
- [Changelog](https://github.com/less/less.js/blob/master/CHANGELOG.md)
- [Commits](less/less.js@v3.11.1...v4.1.1)

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

graylog2-web-interface/package.json

@@ -146,7 +146,7 @@
     "glob": "^7.0.0",
     "html-webpack-plugin": "^4.2.0",
     "json-loader": "^0.5.3",
-    "less": "^3.0.1",
+    "less": "^4.1.1",
     "less-loader": "^7.0.0",
     "node-fetch": "^2.6.1",
     "puppeteer": "^2.1.1",