Update CHANGELOG.md

fix link

Author: MHindermann

CHANGELOG.md

@@ -34,6 +34,6 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - Materials for a crash-course entitled "Clean Code, Documentation & Version Control" at the University of Basel's Graduate School of Business and Economics (GSBE) on February 17, 2023.
 
 [unreleased]: https://github.com/RISE-UNIBAS/clean-code/compare/0.2.0...HEAD
-[0.2.0]: https://github.com/RISE-UNIBAS/clean-code/compare/0.1.0...0.2.0
+[0.2.0]: https://github.com/RISE-UNIBAS/clean-code/compare/0.1.1...0.2.0
 [0.1.1]: https://github.com/RISE-UNIBAS/clean-code/compare/0.1.0...0.1.1
 [0.1.0]: https://github.com/RISE-UNIBAS/clean-code/releases/tag/0.1.0