docs: Including coverage status badge to README.md

Author: BrunoSilvaAndrade

README.md

@@ -3,6 +3,7 @@ Python-config-parser
 ---
 [![Tests](https://github.com/BrunoSilvaAndrade/python-config-parser/actions/workflows/tests.yml/badge.svg)](https://github.com/BrunoSilvaAndrade/python-config-parser/actions/workflows/tests.yml)
 [![PyPI version](https://badge.fury.io/py/python-config-parser.svg)](https://badge.fury.io/py/python-config-parser)
+[![Coverage Status](https://coveralls.io/repos/github/BrunoSilvaAndrade/python-config-parser/badge.svg)](https://coveralls.io/github/BrunoSilvaAndrade/python-config-parser)
 
 This project was created to give you the possibility
 of creating runtime configuration objects using json or yaml files.