Release 1.2.2 (#279)

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CHANGELOG.md

@@ -4,7 +4,7 @@ Changelog for the runtimes governed by the Polkadot Fellowship.
 
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/).
 
-## [Unreleased]
+## [1.2.2] 20.04.2024
 
 ### Fixed