Update CHANGELOG.md

Author: 2No2Name

CHANGELOG.md

@@ -4,13 +4,10 @@ _LithiumVersion_ is automatically replaced with the lithium version, e.g. 0.14.5
 Everything above the line is ignored and not included in the changelog. Everything below will be in the
 changelog on GitHub, Modrinth and CurseForge.
 ----------
-Lithium _LithiumVersion_ for Minecraft _MCVersion_ includes a few bug fixes.
+Lithium _LithiumVersion_ is the first release for Minecraft _MCVersion_.
 
 Make sure to take a backup of your world before using the mod and please report any bugs and mod compatibility issues at the [issue tracker](https://github.com/CaffeineMC/lithium-fabric/issues). You can check the [description of each optimization](https://github.com/CaffeineMC/lithium/blob/_ReleaseTag_/lithium-mixin-config.md) and how to disable it when encountering a problem.
 
-## Additions
-- Include Warden and Creaking in cramming optimization
-
-## Fixes
-- Fix entity explosion exposure optimization not using the entity collision context
-- Fix initialization of cached block info not working on neoforge
+## Changes
+- Update to 1.21.5
+- Migrate tests to vanilla redstone test system