chore: added banner mentioning new edition

Author: lmammino

src/index.html.njk

@@ -15,6 +15,10 @@ og_type:
 {% from "analytics.njk" import track with context %}
 <main>
   <section id="hero" class="hero bg-green bd-rd">
+    <div class="notification is-warning has-text-centered" style="padding: 1.3rem 1rem 1rem">
+      <strong>A new edition of this book is coming out soon and this website is getting updated. <a target="_blank" rel="noopener noreferrer" href="https://www.packtpub.com/en-us/product/nodejs-design-patterns-9781803235431?ref=nodejsdesignpatterns.com" class="has-text-link">Pre-order the new edition!</a>
+      </strong>
+    </div>
     <div class="hero-body">
       <div class="container">
         <div class="columns is-vcentered is-gapless">