chore(package): update mocha to version 7.0.1

Closes #317

Author: greenkeeper[bot]

package.json

@@ -56,7 +56,7 @@
     "jsdom": "^13.1.0",
     "jshint": "^2.9.7",
     "json-stable-stringify": "^1.0.1",
-    "mocha": "^5.2.0",
+    "mocha": "^7.0.1",
     "npm-run-all": "^4.1.5",
     "nyc": "^13.1.0",
     "proxyquire": "^2.1.0",