prepare 0.4.0 release

Author: florian-huber

CHANGELOG.md

@@ -7,7 +7,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
-## [0.4.0] - 2023-04-18
+## [0.4.0] - 2023-04-25
 
 ### Added
 
@@ -114,7 +114,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - This is the initial version of MS2DeepScore
 
 [Unreleased]: https://github.com/matchms/ms2deepscore/compare/0.4.0...HEAD
-[0.4.0]: https://github.com/matchms/ms2deepscore/compare/0.3.1...0.3.1
+[0.4.0]: https://github.com/matchms/ms2deepscore/compare/0.3.1...0.4.0
 [0.3.1]: https://github.com/matchms/ms2deepscore/compare/0.3.1...0.3.1
 [0.3.0]: https://github.com/matchms/ms2deepscore/compare/0.2.3...0.3.0
 [0.2.3]: https://github.com/matchms/ms2deepscore/compare/0.2.2...0.2.3