Add CHANGELOG entry

CHANGELOG.md

@@ -6,8 +6,14 @@ and this project adheres to
 
 ## [Unreleased]
 
-- Replaxe axios with cross-fetch ([#1645])
+### Changed
 
+- Replaxe axios with cross-fetch ([#1645])
+- Fix block events in CometBFT 0.38 API (`begin_block_events`/`end_block_events`
+  -> `finalize_block_events`) in `RpcBlockResultsResponse` and
+  `BlockResultsResponse` ([#1612])
+
+[#1612]: https://github.com/cosmos/cosmjs/pull/1612
 [#1645]: https://github.com/cosmos/cosmjs/pull/1645
 
 ## [0.33.1] - 2025-03-12