Update README.md (#231)

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# Motivation
<!-- Why is this change necessary? -->

# Content
<!-- Please include a summary of the change -->
# Testing
<!-- How was the change tested? -->
# Please check the following before marking your PR as ready for review

- [ ] I have added tests for my changes
- [ ] I have updated the documentation or added new documentation as
needed

Author: joelaguero

README.md

@@ -2,7 +2,7 @@
 
 <p align="center">
   <a href="https://docs.codegen.com">
-    <img src="https://i.imgur.com/ttPWzlG.jpeg" />
+    <img src="https://i.imgur.com/6RF9W0z.jpeg" />
   </a>
 </p>