Merge pull request #128 from sony/feature/20240808-add-isort-badge

Add isort badge

README.md

@@ -3,6 +3,7 @@
 [![Documentation Status](https://readthedocs.org/projects/nnabla-rl/badge/?version=latest)](https://nnabla-rl.readthedocs.io/en/latest/?badge=latest)
 [![Doc style](https://img.shields.io/badge/%20style-google-3666d6.svg)](https://google.github.io/styleguide/pyguide.html#s3.8-comments-and-docstrings)
 [![Code style: black](https://img.shields.io/badge/code%20style-black-000000.svg)](https://github.com/psf/black)
+[![Imports: isort](https://img.shields.io/badge/%20imports-isort-%231674b1?style=flat&labelColor=ef8336)](https://pycqa.github.io/isort/)
 
 # Deep Reinforcement Learning Library built on top of Neural Network Libraries