Fix dependabot issue from https://github.com/microsoft/tsdoc/pull/257

playground/package.json

@@ -32,7 +32,7 @@
     "handlebars-loader": "~1.7.1",
     "handlebars": "~4.7.3",
     "html-webpack-plugin": "~3.2.0",
-    "node-sass": "~4.12.0",
+    "node-sass": "~4.14.1",
     "raw-loader": "~0.5.1",
     "sass-loader": "~7.1.0",
     "style-loader": "~0.23.1",