chore: Prepare release 1.2.3

Author: pawamoy

CHANGELOG.md

@@ -6,6 +6,14 @@ 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).
 
 <!-- insertion marker -->
+## [1.2.3](https://github.com/mkdocstrings/griffe2md/releases/tag/1.2.3) - 2025-09-09
+
+<small>[Compare with 1.2.2](https://github.com/mkdocstrings/griffe2md/compare/1.2.2...1.2.3)</small>
+
+### Bug Fixes
+
+- De-duplicate summary sections when they already exist in the docstring ([6133b2a](https://github.com/mkdocstrings/griffe2md/commit/6133b2af1e404f97c8a5154d22988bdb52982599) by Timothée Mazzucotelli). [Issue-12](https://github.com/mkdocstrings/griffe2md/issues/12)
+
 ## [1.2.2](https://github.com/mkdocstrings/griffe2md/releases/tag/1.2.2) - 2025-08-24
 
 <small>[Compare with 1.2.1](https://github.com/mkdocstrings/griffe2md/compare/1.2.1...1.2.2)</small>