fix: add the badges to the readme (#259)

README.md

@@ -1,5 +1,14 @@
 # Jupyter Sphinx Extensions
 
+[![BSD licence](https://img.shields.io/badge/License-BSD3-yellow.svg?logo=opensourceinitiative&logoColor=white)](LICENSE)
+[![black](https://img.shields.io/badge/code%20style-black-000000)](https://github.com/psf/black)
+[![prettier](https://img.shields.io/badge/code_style-prettier-ff69b4.svg?logo=prettier&logoColor=white)](https://github.com/prettier/prettier)
+[![pre-commit](https://img.shields.io/badge/pre--commit-active-yellow?logo=pre-commit&logoColor=white)](https://pre-commit.com/)
+[![pypi version](https://img.shields.io/pypi/v/jupyter-sphinx?color=blue&logo=pypi&logoColor=white)](https://pypi.org/project/jupyter-sphinx/)
+[![conda-forge version badge](https://img.shields.io/conda/vn/conda-forge/jupyter-sphinx?logo=anaconda&logoColor=white&color=blue)](https://anaconda.org/conda-forge/jupyter-sphinx)
+[![tests](https://img.shields.io/github/actions/workflow/status/jupyter/jupyter-sphinx/tests.yml?logo=github&logoColor=white)](https://github.com/jupyter/jupyter-sphinx/actions/workflows/tests.yml)
+[![docs](https://img.shields.io/readthedocs/jupyter-sphinx?logo=readthedocs&logoColor=white)](https://jupyter-sphinx.readthedocs.io/)
+
 `jupyter-sphinx` enables running code embedded in Sphinx documentation and
 embedding output of that code into the resulting document. It has support
 for rich output such as images and even Jupyter interactive widgets.