Update CHANGELOG for gradlew guard fix

Author: Malax

CHANGELOG.md

@@ -6,6 +6,9 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.1.0/).
 
 ## [Unreleased]
 
+### Fixed
+
+- Guard against missing gradlew during daemon cleanup to prevent "No such file or directory" errors. ([#172](https://github.com/heroku/heroku-buildpack-gradle/pull/172))
 
 ## [v45] - 2025-09-12