Update mocha to the latest version 🚀 (#21)

Author: greenkeeper[bot]

packages/google-cloud-vision/package.json

@@ -75,7 +75,7 @@
     "ink-docstrap": "^1.3.0",
     "intelli-espower-loader": "^1.0.1",
     "jsdoc": "^3.5.5",
-    "mocha": "^4.0.1",
+    "mocha": "^5.0.0",
     "node-uuid": "^1.4.7",
     "nyc": "^11.3.0",
     "power-assert": "^1.4.4",