Prepare 1.0.0 release

Author: erickskrauch

CHANGELOG.md

@@ -4,6 +4,10 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](http://keepachangelog.com/en/1.0.0/)
 and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.html).
 
-## Unreleased
+## [Unreleased]
+
+## 1.0.0 - 2023-05-17
 ### Added
 - Initial implementation (extracted from [`elyby/php-code-style`](https://github.com/elyby/php-code-style/tree/0.5.0)).
+
+[Unreleased]: https://github.com/erickskrauch/php-cs-fixer-custom-fixers/compare/1.0.0...HEAD