update changelog

Author: RobinMalfait

CHANGELOG.md

@@ -10,6 +10,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 ### Fixed
 
 - Discard invalid classes such as `bg-red-[#000]` ([#13970](https://github.com/tailwindlabs/tailwindcss/pull/13970))
+- Discard invalid `variants` and `utilities` with modifiers ([#13977](https://github.com/tailwindlabs/tailwindcss/pull/13977))
 
 ## [4.0.0-alpha.17] - 2024-07-04