chore(package): update mocha to version 7.1.1

Closes #101

Author: greenkeeper[bot]

package.json

@@ -24,7 +24,7 @@
   "devDependencies": {
     "chai": "^4.1.0",
     "istanbul": "^0.4.5",
-    "mocha": "^5.0.0",
+    "mocha": "^7.1.1",
     "pre-commit": "^1.2.2",
     "sinon": "^4.0.0",
     "sinon-chai": "^2.8.0"