chore(package): update mocha to version 7.1.1

Closes #139

Author: greenkeeper[bot]

package.json

@@ -54,7 +54,7 @@
     "file-type": "^12.3.0",
     "husky": "^3.0.8",
     "jshint": "^2.10.2",
-    "mocha": "^6.2.1",
+    "mocha": "^7.1.1",
     "prettier-standard": "^15.0.1",
     "standard": "^14.3.1"
   }