release: Update CHANGELOG.md for 0.6.1

Author: ManifoldFR

CHANGELOG.md

@@ -7,6 +7,8 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
+## [0.6.1] - 2024-05-13
+
 ### Changed
 
 * Changes to includes and tests for linesearch methods ([#81](https://github.com/Simple-Robotics/proxsuite-nlp/pull/81))
@@ -81,7 +83,8 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 * This is the first release of `proxsuite-nlp`. This library is a joint effort between LAAS-CNRS and INRIA, and will be maintained and expanded in the future. Please provide constructive feedback and contribute!
 
-[Unreleased]: https://github.com/Simple-Robotics/proxsuite-nlp/compare/v0.6.0...HEAD
+[Unreleased]: https://github.com/Simple-Robotics/proxsuite-nlp/compare/v0.6.1...HEAD
+[0.6.1]: https://github.com/Simple-Robotics/proxsuite-nlp/compare/v0.6.0...v0.6.1
 [0.6.0]: https://github.com/Simple-Robotics/proxsuite-nlp/compare/v0.5.0...v0.6.0
 [0.5.0]: https://github.com/Simple-Robotics/proxsuite-nlp/compare/v0.4.0...v0.5.0
 [0.4.0]: https://github.com/Simple-Robotics/proxsuite-nlp/compare/v0.3.4...v0.4.0