Add maintainability badge

Author: thedoorbell

README.md

@@ -1,2 +1,5 @@
 ### Hexlet tests and linter status:
-[![Actions Status](https://github.com/thedoorbell/fullstack-javascript-project-44/actions/workflows/hexlet-check.yml/badge.svg)](https://github.com/thedoorbell/fullstack-javascript-project-44/actions)
+
+[![Actions Status](https://github.com/thedoorbell/fullstack-javascript-project-44/actions/workflows/hexlet-check.yml/badge.svg)](https://github.com/thedoorbell/fullstack-javascript-project-44/actions)
+
+[![Maintainability](https://api.codeclimate.com/v1/badges/df7e831b6780077b35d8/maintainability)](https://codeclimate.com/github/thedoorbell/fullstack-javascript-project-44/maintainability)