update README

Author: Nurzhan2023

README.md

@@ -1,4 +1,6 @@
 ### Hexlet tests and linter status:
+[![Maintainability](https://api.codeclimate.com/v1/badges/b23c691de6b894bf85ac/maintainability)](https://codeclimate.com/github/Nurzhan2023/python-project-50/maintainability)
+
 [![Actions Status](https://github.com/Nurzhan2023/python-project-50/actions/workflows/hexlet-check.yml/badge.svg)](https://github.com/Nurzhan2023/python-project-50/actions)
 
 [![Python CI](https://github.com/Nurzhan2023/python-project-50/actions/workflows/python-ci.yml/badge.svg)](https://github.com/Nurzhan2023/python-project-50/actions/workflows/python-ci.yml)