Update banner with new website link

Author: Qianqianye

src/templates/partials/header.hbs

@@ -14,6 +14,6 @@ title: header
   <a tabindex="1" href="#content" id="skip-to-content">Skip to main content</a>
 
   {{!-- <a id="promo-link" href="https://processingfoundation.org/grants" target="_blank"><div id="promo">Apply to the $10k pr05 grant by May 31!</div></a> --}}
-  {{!-- <a id="promo-link" href="https://donorbox.org/to-the-power-of-10" target="_blank"><div id="promo">Support p5.js and the Processing Foundation and earn unique rewards.🎉</div></a> --}}
+  <a id="promo-link" href="https://p5js.org" target="_blank"><div id="promo">This site is archived. Visit the new p5.js website at p5js.org 🎉.</div></a>
 
 </nav>