chore(package): update mocha to version 6.0.0

Author: greenkeeper[bot]

package.json

@@ -32,7 +32,7 @@
 	},
 	"devDependencies": {
 		"eslint-config-fnd": "^1.6.0",
-		"mocha": "^5.2.0",
+		"mocha": "^6.0.0",
 		"npm-run-all": "^4.1.5",
 		"release-util-fnd": "^1.1.1"
 	}