chore(package): update mocha to version 6.2.0

Closes #31

Author: greenkeeper[bot]

Diff for: package.json

@@ -31,7 +31,7 @@
     "@types/sequelize": "^4.0.79",
     "chai": "^4.1.2",
     "mkdirp": "^0.5.1",
-    "mocha": "^5.0.0",
+    "mocha": "^6.2.0",
     "nyc": "^12.0.1",
     "request": "^2.83.0",
     "rimraf": "^2.6.2",