fix: upgrade node-sass from 4.13.1 to 4.14.0

Snyk has created this PR to upgrade node-sass from 4.13.1 to 4.14.0.

See this package in NPM:
https://www.npmjs.com/package/node-sass

See this project in Snyk:
https://app.snyk.io/org/ovlb/project/75122d17-d389-4779-977f-1027eef36940?utm_source=github&utm_medium=upgrade-pr

package.json

@@ -24,7 +24,7 @@
     "contentful": "^7.14.2",
     "cross-env": "^5.2.0",
     "marked": "^0.8.0",
-    "node-sass": "^4.12.0",
+    "node-sass": "^4.14.0",
     "nuxt": "^2.10.2",
     "prism-themes": "^1.3.0",
     "prismjs": "^1.20.0",