Fix broken links (#16747)

Signed-off-by: Ajay Singh <37625112+Ajay-singh1@users.noreply.github.com>

Author: Ajay-singh1

layouts/_default/baseof.html

@@ -40,7 +40,7 @@
             <meta property="og:image" content="https://raw.githubusercontent.com/istio/istio.io/master/static/img/istio-social.png">
             <meta property="og:image:alt" content="The Istio sailboat logo">
             <meta property="og:image:width" content="4096">
-            <meta property="og:image:height" content="2048">    
+            <meta property="og:image:height" content="2048">
         {{ end }}
         <meta property="og:site_name" content="Istio">
 
@@ -161,7 +161,10 @@
         {{ if and (eq .Section "docs") .Site.Data.args.archive}}
         <div class="archive-warning-banner" role="alert">
             {{ (printf (i18n "archive_banner_text") .Site.Data.args.version) | safeHTML }}
-            <a href="/latest{{ .RelPermalink | safeURL }}">{{ i18n "archive_banner_link" }}</a>
+            {{ $rel := .RelPermalink }}
+            {{ $path := replaceRE `^/v[0-9]+\.[0-9]+/` "" $rel }}
+            {{ $latestURL := printf "https://istio.io/latest/%s" $path }}
+            <a href="{{ $latestURL | safeURL }}">{{ i18n "archive_banner_link" }}</a>
         </div>
         {{ end }}