docs(discord): Add Discord badge in README (#530)

Fixing #529

Co-authored-by: Matt J. <[email protected]>

README.md

@@ -4,6 +4,7 @@
 ![python](https://img.shields.io/badge/python-3.9%20%7C%203.10%20%7C%203.11%20%7C%203.12-blue?style=flat&logo=python)
 [![pypi](https://img.shields.io/pypi/v/skore)](https://pypi.org/project/skore/)
 ![license](https://img.shields.io/pypi/l/skore)
+[![Discord](https://img.shields.io/badge/Discord-%235865F2.svg?logo=discord&logoColor=white)](https://discord.probabl.ai/)
 
 With `skore`, data scientists can:
 1. Store objects of different types from their Python code: python lists, `scikit-learn` fitted pipelines, `plotly` figures, and more.