feat: rename workflows and add badges

Signed-off-by: Charles Larivier <charles@dribbble.com>

Author: Charles Larivier

.github/workflows/python-package.yml renamed to .github/workflows/main.yml

@@ -1 +1,4 @@
 # Metabase Python
+[![main](https://github.com/chasleslr/metabase-python/actions/workflows/main.yml/badge.svg?branch=main)](https://github.com/chasleslr/metabase-python/actions/workflows/main.yml)
+[![codecov](https://codecov.io/gh/chasleslr/metabase-python/branch/main/graph/badge.svg?token=15G7HOQ1CM)](https://codecov.io/gh/chasleslr/metabase-python)
+[![Code style: black](https://img.shields.io/badge/code%20style-black-000000.svg)](https://github.com/psf/black)