update docs

Author: Schmaetz

docs/hugo/content/en/release_notes/_index.md

@@ -14,13 +14,17 @@ weight: 2500
 #### Changes
 - Add OwnerReference for Statefulsets
 - Optimisations for major upgrade
+- Statefulsert receives OwnerReference to the CR
 
 #### Fixes
 - cert-Handling for Multisite
 - pgBackRest Restore with TDE
 - Fix for Monitoring pgBackRest
 - Dependency updates and several small changes
 
+#### Notification of upcoming deprecation
+- PG13 has reached its EoL 
+
 #### Supported Versions
 
 - PG: 13 - 18