Fix duplicate entry in CHANGELOG

Author: dbanty

CHANGELOG.md

@@ -36,7 +36,6 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - Update minimum Pydantic version to support Python 3.9
 
 ### Additions
-- Better compatibility for "required" (whether or not the field must be included) and "nullable" (whether or not the field can be null) (#205 & #208). Thanks @bowenwr & @emannguitar!
 
 - Allow specifying the generated client's version using `package_version_override` in a config file. (#225 - Thanks @fyhertz!)