Upgraded grunt-contrib-qunit to use puppeteer.

package.json

@@ -12,6 +12,6 @@
     "eslint": "^6.8.0",
     "grunt": "^1.0.1",
     "grunt-cli": "^1.2.0",
-    "grunt-contrib-qunit": "^1.2.0"
+    "grunt-contrib-qunit": "^3.1.0"
   }
 }