⚙️ ci(cover): Add cover script.

Author: make-github-pseudonymous-again

package.json

@@ -67,6 +67,7 @@
  },
  "scripts": {
  "build": "rm -rf lib && babel src -d lib",
+ "cover": "nyc --reporter=lcov npm test",
  "esdoc": "esdoc",
  "prepare": "npm run build",
  "release": "np",