add link to sql db

Author: JnHs

articles/copilot/capabilities.md

@@ -31,6 +31,7 @@ Use Microsoft Copilot for Azure (preview) to perform many basic tasks. There are
   - [Get information about Azure Monitor metrics and logs](get-monitoring-information.md)
   - [Work smarter with Azure Stack HCI](work-smarter-edge.md)
   - [Secure and protect storage accounts](improve-storage-accounts.md)
+  - [Improve Azure SQL Database-driven applications](/azure/azure-sql/copilot/copilot-azure-sql-overview)
 - Write and optimize code:
   - [Generate Azure CLI scripts](generate-cli-scripts.md)
   - [Discover performance recommendations with Code Optimizations](optimize-code-application-insights.md)