Prepare release 0.9.1

This is a breaking change, 0.9.0 should be yanked. See
#568

Author: sosthene-nitrokey

CHANGELOG.md

@@ -5,7 +5,7 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](http://keepachangelog.com/)
 and this project adheres to [Semantic Versioning](http://semver.org/).
 
-## [Unreleased]
+## [v0.9.1] - 2025-04-28
 
 ### Changed
 

Cargo.toml

@@ -12,7 +12,7 @@ keywords = ["static", "no-heap"]
 license = "MIT OR Apache-2.0"
 name = "heapless"
 repository = "https://github.com/rust-embedded/heapless"
-version = "0.9.0"
+version = "0.9.1"
 
 [features]
 bytes = ["dep:bytes"]