Update release-notes.md

added one item that we missed.
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cc: @twright-msft

Author: dnethi

articles/azure-arc/data/release-notes.md

@@ -29,6 +29,7 @@ New for this release:
 
 - Azure Arc-enabled SQL Managed Instance
   - Direct mode for failover groups is generally available az CLI
+  - Schedule the HA orchestrator replicas on different nodes when available
 
 - Arc PostgreSQL
   - Ensure postgres extensions work per database/role