Update CHANGELOG.md

Author: mrcjkb

CHANGELOG.md

@@ -8,8 +8,11 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
+### Fixed
+
 - Made the `mod` snippet handle the case where the module declaration already
   exists.
+  Thanks [@gregorias](https://github.com/gregorias)!
 
 ## [1.4.1] - 2023-12-05