Compress banner to WebP (11MB PNG -> 487KB WebP)

Resize to 2000px wide at q=82 and drop the unused banner.jpeg.

Author: Codegass

website/assets/banner.jpeg

@@ -394,7 +394,7 @@ header.g {
 @keyframes blink { 50% { opacity: 0; } }
 
 .demo-side {
-  background: url('../assets/banner2.png') center/cover no-repeat;
+  background: url('../assets/banner2.webp') center/cover no-repeat;
   position: relative;
   min-height: 400px;
   border-left: none !important;