Changelog update for v3.2.2

**Description**
Added detaisl for Health Monitoring Agent updates to changelog

**Testing Done**
Production canary failure fixes validated.

Author: papriwal

CHANGELOG.md

@@ -5,6 +5,7 @@
 ### Features
 
   * Fix for production canary failures caused by bad training job template.
+  * New version for Health Monitoring Agent (1.0.790.0_1.0.266.0) with minor improvements and bug fixes.
 
 ## v3.2.1 (2025-08-27)