feat: upgrade node-sass from 8.0.0 to 9.0.0

Snyk has created this PR to upgrade node-sass from 8.0.0 to 9.0.0.

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

See this project in Snyk:
https://app.snyk.io/org/dlminvestments/project/0a9d4778-6860-473a-be22-d4f19c127a4e?utm_source=github&utm_medium=referral&page=upgrade-pr

Author: snyk-bot

package.json

@@ -16,7 +16,7 @@
   "devDependencies": {
     "chai": "4.3.7",
     "grunt": "1.6.1",
-    "node-sass": "8.0.0",
+    "node-sass": "9.0.0",
     "grunt-available-tasks": "0.6.3",
     "grunt-bower-installer": "0.3.6",
     "grunt-contrib-clean": "2.0.1",