UI: Replace node-sass with sass (Dart Sass)

Note: There are some annoying deprecation warnings
which come from bootstrap. Those can be dealt with
if we upgrade bootstrap.

monkey/monkey_island/cc/ui/package.json

@@ -50,11 +50,11 @@
     "html-loader": "^0.5.5",
     "html-webpack-plugin": "^5.3.2",
     "minimist": "^1.2.5",
-    "node-sass": "^4.14.1",
     "npm": "^7.24.0",
     "null-loader": "^0.1.1",
     "react-addons-test-utils": "^15.6.2",
     "rimraf": "^2.7.1",
+    "sass": "^1.41.1",
     "sass-loader": "^7.3.1",
     "snyk": "^1.716.0",
     "style-loader": "^0.22.1",