add changelog

Author: crodriguezvega

modules/light-clients/08-wasm/CHANGELOG.md

@@ -51,6 +51,7 @@ Ref: https://keepachangelog.com/en/1.0.0/
 ### Features
 
 * [#\5821](https://github.com/cosmos/ibc-go/pull/5821) feat: add `VerifyMembershipProof` RPC query (querier approach for conditional clients).
+* [#\6231](https://github.com/cosmos/ibc-go/pull/6231) feat: add CLI to broadcast transaction with `MsgMigrateContract`.
 
 ### Bug Fixes