Update CHANGELOG

Author: shepherd-l

OneSignalExample/Assets/OneSignal/CHANGELOG.md

@@ -5,6 +5,12 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
 ## [Unreleased]
+### Added
+- Sdk type and version to api headers
+### Changed
+- Updated included Android SDK to [5.0.0-beta2](https://github.com/OneSignal/OneSignal-Android-SDK/releases/tag/5.0.0-beta2)
+- Updated included iOS SDK to [5.0.0-beta-02](https://github.com/OneSignal/OneSignal-iOS-SDK/releases/tag/5.0.0-beta-02)
+
 ## [5.0.0-beta.1]
 ### Added
 - [Migration guide](https://github.com/OneSignal/OneSignal-Unity-SDK/blob/5.0.0-beta.1/MIGRATION_GUIDE_v3_to_v5.md