Update release notes landing page to use version variables (#2447)

This page wasn't using version variables.

---------

Co-authored-by: Vlada Chirmicci <[email protected]>

Author: eedugon

release-notes/intro/index.md

@@ -4,20 +4,20 @@ mapped_pages:
   - https://www.elastic.co/guide/en/elastic-stack/current/elastic-stack-breaking-changes.html
 products:
   - id: elastic-stack
-description: Explore the new features, enhancements, fixes, and deprecations for Elastic Stack 9.0+ (latest 9.1.0), Elastic Cloud Serverless, and...
+description: Explore the new features, enhancements, fixes, and deprecations for Elastic Stack 9.0+ (latest 9.1.1), Elastic Cloud Serverless, and...
 ---
 
 # Elastic release notes [elastic-release-notes]
 
 Stay up to date with the latest changes, fixes, known issues, and deprecations in Elastic products. 
 
 Release notes cover the all the latest Elastic product changes, including the following:
-* {{stack}} 9.0.0 and later, including the most recent 9.1.0 release
+* {{stack}} {{version.stack.base}} and later, including the most recent {{version.stack}} release
 * {{serverless-full}}, including updates to {{es}}, and {{observability}} and {{elastic-sec}} solutions
 
 ## What's new in the latest Elastic release?
 
-Elastic Stack 9.1.0 includes new features, enhancements, and critical fixes across {{es}}, {{observability}}, {{elastic-sec}}, {{kib}}, and more. To view detailed release notes, select a product.
+Elastic Stack {{version.stack}} includes new features, enhancements, and critical fixes across {{es}}, {{observability}}, {{elastic-sec}}, {{kib}}, and more. To view detailed release notes, select a product.
 
 :::{tip}
 Looking for earlier versions? Go to [Release docs](https://www.elastic.co/guide/en/starting-with-the-elasticsearch-platform-and-its-solutions/8.19/new.html).