Updates landing page and conf.yaml to specify Elastic Stack 8.19 and earlier (#3247)

* Updates landing page and conf.yaml to specify Elastic Stack 8.19 and earlier

* Removes attributes

* Removes all SEO meta data from conf.yaml

* Updates latest Elastic version

Author: KOTungseth

extra/docs_landing.html

@@ -446,11 +446,21 @@
 </style>
 
 <div class="old-elastic-experience-warning">
-  You are viewing the previous version of Elastic docs. To view the current docs, go to <a href="https://www.elastic.co/docs">elastic.co/docs</a>.
+  You are viewing previous versions of the Elastic Docs. To view the latest versions, go to <a href="https://www.elastic.co/docs">elastic.co/docs</a>.
 </div>
 
 <div class="legalnotice"></div>
 
+<div class="row my-4">
+  <div class="col">
+    <p>
+      Welcome to the docs that cover all changes in Elastic Stack 8.19 and earlier.
+      To view the docs for the latest Elastic product versions, including Elastic Stack 9.1 and Elastic Cloud Serverless,
+      go to <a href="https://www.elastic.co/docs">elastic.co/docs</a>.
+    </p>
+  </div>
+</div>
+
 <div id="subnavigation" class="subnavigation">
   <p>
     <a class="inline-block mr-3" href="https://www.elastic.co/guide/index.html#viewall">Browse all docs</a>