Update mocha

Author: ctimmerm

package.json

@@ -45,7 +45,7 @@
     "cross-env": "^5.1.0",
     "eslint": "^4.3.0",
     "istanbul": "^0.4.5",
-    "mocha": "^4.0.1",
+    "mocha": "^5.0.0",
     "rimraf": "^2.6.1",
     "webpack": "^3.3.0"
   },