docs: update changelog entry

Author: boray

CHANGELOG.md

@@ -63,8 +63,6 @@ This project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.htm
   repository proof-systems. https://github.com/o1-labs/o1js/pull/2128
 - Added verification key validity checks to `LocalBlockchain`. https://github.com/o1-labs/o1js/pull/2171
 
-### Fixed
-
 ## [2.4.0](https://github.com/o1-labs/o1js/compare/fb625f...6ff7f8470a) - 2025-04-01
 
 ### Added