Change Mendix Cloud GenAI Resource Packs Guardrails to Private Beta

Updated the availability status of Mendix Cloud GenAI Resource Packs Guardrails from Public Beta to Private Beta.

Author: Karuna-Mendix

content/en/docs/releasenotes/feature-release-calendar/_index.md

@@ -25,7 +25,7 @@ General Availability means that a feature is available for all users. This type
 | MCP Server                                    | General Availability: Mx 11.0 + Mx 10.24 |
 | MCP Client                                    | General Availability: Mx 11.2 + Mx 10.24 |
 | Mendix Cloud GenAI Resource Packs             | General Availability: Mx 11.2 + Mx 10.24 |
-| Mendix Cloud GenAI Resource Packs Guardrails  | Public Beta: Mx 11.12 |
+| Mendix Cloud GenAI Resource Packs Guardrails  | Private Beta: Mx 11.15 |
 | Agent Editor in Studio Pro<sup>1</sup>        | General Availability: Mx 11.9 |
 | Agent Observability                           | General Availability: Mx 11.5 + Mx 10.24 |
 | Model Mendix Agents as part of your Workflow  | General Availability: Mx 11.9 |