Bump contentctl.yml to 6.0.0 (#4067)

* chore: bump contentctl.yml to 5.28.0

* Update contentctl.yml

Co-authored-by: Nasreddine Bencherchali <nasreddineb@splunk.com>

---------

Co-authored-by: research bot <research@splunk.com>
Co-authored-by: Nasreddine Bencherchali <nasreddineb@splunk.com>

Author: 3 people

contentctl.yml

@@ -3,7 +3,7 @@ app:
   uid: 3449
   title: ES Content Updates
   appid: DA-ESS-ContentUpdate
-  version: 5.27.0
+  version: 6.0.0
   description: Explore the Analytic Stories included with ES Content Updates.
   prefix: ESCU
   label: ESCU