Adding the Ruff badge to project's README.md (#1537)

README.md

@@ -3,6 +3,7 @@
 
 [![Tests](https://github.com/whitphx/streamlit-webrtc/workflows/Tests/badge.svg?branch=main)](https://github.com/whitphx/streamlit-webrtc/actions?query=workflow%3ATests+branch%3Amain)
 [![Frontend Tests](https://github.com/whitphx/streamlit-webrtc/workflows/Frontend%20tests/badge.svg?branch=main)](https://github.com/whitphx/streamlit-webrtc/actions?query=workflow%3A%22Frontend+tests%22+branch%3Amain)
+[![Ruff](https://img.shields.io/endpoint?url=https://raw.githubusercontent.com/astral-sh/ruff/main/assets/badge/v2.json)](https://github.com/astral-sh/ruff)
 
 [![PyPI](https://img.shields.io/pypi/v/streamlit-webrtc)](https://pypi.org/project/streamlit-webrtc/)
 [![PyPI - Python Version](https://img.shields.io/pypi/pyversions/streamlit-webrtc)](https://pypi.org/project/streamlit-webrtc/)