docs: added testing feature and pytest badge in readme

README.md

@@ -5,6 +5,7 @@
 | Languages | [![Python 3.7](https://img.shields.io/badge/Python-3.7-3776AB?logo=python&logoColor=ffdd54)](https://www.python.org/downloads/release/python-370/) [![Markdown](https://img.shields.io/badge/markdown-%23000000.svg?logo=markdown&logoColor=white)](https://daringfireball.net/projects/markdown/) |
 | Git | [![Conventional Commits](https://img.shields.io/badge/Conventional%20Commits-1.0.0-%23FE5196?logo=conventionalcommits&logoColor=white)](https://conventionalcommits.org) |
 | Formatting | [![Black](https://img.shields.io/badge/Code%20Style-black-000000)](https://github.com/psf/black) [![docformatter](https://img.shields.io/badge/Docstring%20Formatter-docformatter-fedcba.svg)](https://github.com/PyCQA/docformatter) [![numpy](https://img.shields.io/badge/Docstring%20Style-numpy-459db9.svg)](https://numpydoc.readthedocs.io/en/latest/format.html) [![Imports: isort](https://img.shields.io/badge/%20Imports-isort-%231674b1?style=flat&labelColor=ef8336)](https://pycqa.github.io/isort/) |
+| Testing | [![Pytest](https://img.shields.io/badge/pytest-%23000000.svg?logo=pytest)](https://docs.pytest.org/)
 
 DAIDE parser using [parsimonious](https://github.com/erikrose/parsimonious). Parsimonious is a python package that uses "a simplified sort of EBNF notation" to define a grammar. The parser currently supports all 130 levels of DAIDE.