Update CHANGELOG for version 2.3.0

Author: ipmb

CHANGELOG.md

@@ -5,6 +5,12 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.1.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
+## [2.3.0] - 2025-09-19
+
+### Added
+
+* apppack.toml file is now accessible by APPPACK_TOML environment variable, allowing different services in different environments. 
+
 ## [2.2.0] - 2025-06-16
 
 ### Changed
@@ -20,9 +26,3 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 ### Fixed
 
 * Release tasks work with latest metadata from Heroku Buildpacks
-
-## [2.2.0] - 2025-09-19
-
-### Added
-
-* apppack.toml file is now accessible by APPPACK_TOML environment variable, allowing different services in different environments.