Update CHANGELOG.md

Author: Cameron-Micka

com.microsoft.mrtk.graphicstools.unity/CHANGELOG.md

@@ -4,6 +4,12 @@ All notable changes to this package will be documented in this file.
 
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.1.0/).
 
+## [0.7.1] - 2024-05-22
+
+### Changed
+
+- Fixed Unity 2023 Text Mesh Pro rendering issues.
+
 ## [0.7.0] - 2024-05-07
 
 ### Changed