Update README.md
correct the url of databend logo
<div align="center">
-<p align="center"><img alt="Databend Logo" src="website/databend/static/img/favicon.png" width="20%"/></p>
+<p align="center"><img alt="Databend Logo" src="website/static/img/favicon.png" width="20%"/></p>
<p align="center">The Open Source Serverless Data Warehouse for Everyone</p>
<h4 align="center">
