Remove 1.4 announcement

Author: cwickham

_quarto.yml

@@ -51,9 +51,6 @@ website:
       - icon: rss
         href: https://quarto.org/docs/blog/index.xml
         aria-label: Quarto Blog RSS
-  announcement: 
-    content: "🎉 Quarto 1.4 released! [Download](/docs/download/), [Read More](/docs/blog/posts/2024-01-24-1.4-release/)"
-    position: below-navbar
   navbar:
     background: light
     logo: quarto.png