chore(package): update mocha to version 7.1.0

Closes #30

Author: greenkeeper[bot]

package.json

@@ -33,7 +33,7 @@
     "jshint": "^2.9.0",
     "jshint-stylish": "^2.0.0",
     "load-grunt-tasks": "^3.0.0",
-    "mocha": "^3.4.2",
+    "mocha": "^7.1.0",
     "require-uncached": "^1.0.2"
   },
   "peerDependencies": {