Update changelog for release

Author: paulbalandan

CHANGELOG.md

@@ -5,6 +5,12 @@ All notable changes to this library will be documented in this file:
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/)
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
+## [v2.1.1](https://github.com/NexusPHP/cs-config/compare/v2.1.0..v2.1.1) - 2020-12-12
+
+### Changed
+
+- `increment_style` fixer now uses the `['style' => 'pre']`. Previously, this was `post`.
+
 ## [v2.1.0](https://github.com/NexusPHP/cs-config/compare/v2.0.2..v2.0.2) - 2020-12-08
 
 ### Added