chore: add changelog item

Author: a7medev

CHANGELOG.md

@@ -1,5 +1,11 @@
 # Changelog
 
+## [Unreleased](https://github.com/Instabug/Instabug-Flutter/compare/v13.3.0...dev)
+
+### Added
+
+- Add support for masking screen names captured by Instabug through the `Instabug.setScreenNameMaskingCallback` API ([#500](https://github.com/Instabug/Instabug-Flutter/pull/500)).
+
 ## [13.3.0](https://github.com/Instabug/Instabug-Flutter/compare/v13.2.0...v13.3.0) (August 5, 2024)
 
 ### Added