chore(package): update mocha to version 7.2.0

Closes #32

Author: greenkeeper[bot]

package.json

@@ -50,7 +50,7 @@
     "eslint": "^5.3.0",
     "eslint-config-prettier": "^3.0.0",
     "eslint-plugin-prettier": "^2.6.2",
-    "mocha": "^6.0.0",
+    "mocha": "^7.2.0",
     "nyc": "^12.0.2",
     "prettier": "^1.14.0",
     "rimraf": "^2.6.1"