MOD: Add logo to Python client README.md

Author: nmacholl

README.md

@@ -1,4 +1,12 @@
-# databento-python
+<a href="https://databento.com">
+  <picture>
+    <source media="(prefers-color-scheme: dark)" srcset="https://dzv012k6yye9u.cloudfront.net/brand/logo-white.png">
+    <source media="(prefers-color-scheme: light)" srcset="https://dzv012k6yye9u.cloudfront.net/brand/logo.png">
+    <img alt="Databento" src="https://dzv012k6yye9u.cloudfront.net/brand/logo-white.png" width="560px">
+  </picture>
+</a>
+
+# Pay as you go for market data
 
 [![test](https://github.com/databento/databento-python/actions/workflows/test.yml/badge.svg?branch=dev)](https://github.com/databento/databento-python/actions/workflows/test.yml)
 ![python](https://img.shields.io/badge/python-3.8+-blue.svg)