Update changelog

Author: acelaya

CHANGELOG.md

@@ -15,6 +15,7 @@ The format is based on [Keep a Changelog](https://keepachangelog.com), and this
 
 * [#2540](https://github.com/shlinkio/shlink/issues/2540) Update Symfony packages to 8.0.
 * [#2512](https://github.com/shlinkio/shlink/issues/2512) Make all remaining console commands invokable.
+* [#2555](https://github.com/shlinkio/shlink/issues/2555) Update docker image to PHP 8.5.
 
 ### Deprecated
 * *Nothing*