docs: update changelog for 0.5.6 release

CHANGELOG.md

@@ -2,6 +2,8 @@
 All notable changes to this project will be documented in this file. This change log follows the conventions of [keepachangelog.com](http://keepachangelog.com/).
 
 ## [Unreleased]
+
+## [0.5.6] - 2024-12-23
 - Updated kotlin version to `2.1.0`
 - Updated `kotlinx.serialization` version to `1.7.3`
 - Improved performance and heap usage of serialization by creating less byte objects ([#102][p102])
@@ -107,7 +109,7 @@ MsgPack.default.encodeToByteArray(...)
 - `MsgPackDynamicSerializer` as placeholder for future [contextual serializer](https://github.com/Kotlin/kotlinx.serialization/blob/master/docs/serializers.md#contextual-serialization)
 - Full implementation of msgpack spec excluding extension types and bin format family
 
-[Unreleased]: https://github.com/esensar/kotlinx-serialization-msgpack/compare/0.5.5...main
+[Unreleased]: https://github.com/esensar/kotlinx-serialization-msgpack/compare/0.5.6...main
 [0.2.0]: https://github.com/esensar/kotlinx-serialization-msgpack/compare/0.1.0...0.2.0
 [0.2.1]: https://github.com/esensar/kotlinx-serialization-msgpack/compare/0.2.0...0.2.1
 [0.3.0]: https://github.com/esensar/kotlinx-serialization-msgpack/compare/0.2.1...0.3.0
@@ -122,6 +124,7 @@ MsgPack.default.encodeToByteArray(...)
 [0.5.3]: https://github.com/esensar/kotlinx-serialization-msgpack/compare/0.5.2...0.5.3
 [0.5.4]: https://github.com/esensar/kotlinx-serialization-msgpack/compare/0.5.3...0.5.4
 [0.5.5]: https://github.com/esensar/kotlinx-serialization-msgpack/compare/0.5.4...0.5.5
+[0.5.6]: https://github.com/esensar/kotlinx-serialization-msgpack/compare/0.5.5...0.5.6
 [i6]: https://github.com/esensar/kotlinx-serialization-msgpack/issues/6
 [i9]: https://github.com/esensar/kotlinx-serialization-msgpack/issues/9
 [i10]: https://github.com/esensar/kotlinx-serialization-msgpack/issues/10