update readme logo

Author: pfvatterott

README.md

@@ -1,6 +1,6 @@
 <p align="center">
   <a href="https://www.propelauth.com?ref=github" target="_blank" align="center">
-    <img src="https://propelauth-logos.s3.us-west-2.amazonaws.com/logo-only.png" width="100">
+    <img src="https://www.propelauth.com/imgs/lockup.svg" width="200">
   </a>
 </p>