chore(package): update mocha to version 7.2.0

Closes #41

Author: greenkeeper[bot]

package.json

@@ -55,7 +55,7 @@
     "eslint-plugin-promise": "^4.2.1",
     "eslint-plugin-standard": "^4.0.1",
     "json-stable-stringify": "^1.0.1",
-    "mocha": "^6.2.2",
+    "mocha": "^7.2.0",
     "nyc": "^14.1.1",
     "stream-to-string": "^1.2.0",
     "thought": "^2.0.0",