chore(package): update mocha to version 7.2.0

Closes #58

Author: greenkeeper[bot]

package.json

@@ -47,7 +47,7 @@
     "chai": "^4.1.2",
     "coveralls": "^3.0.2",
     "husky": "^3.0.0",
-    "mocha": "^6.1.4",
+    "mocha": "^7.2.0",
     "nyc": "^14.1.1",
     "standard": "^12.0.1"
   }