Add AgentKit Banner to ReadMe (#122)

* Add files via upload

Add AgentKit banner

* Update README.md

Author: jln07

README.md

@@ -1,4 +1,9 @@
 <div align="center">
+  <p>
+    <a href="https://docs.cdp.coinbase.com/agentkit/docs/welcome">
+      <img src="./agentkit_banner.png"/>
+    </a>
+  </p>
   <h1 style="font-size: 3em; margin-bottom: 20px;">
     AgentKit
   </h1>