message: Add CHANGELOG entry for CommitSignature change
diff: @@ -10,6 +10,11 @@ and this project adheres to
  - @cosmjs/cosmwasm-stargate: Codec adapted to support wasmd 0.16. Older versions
  of wasmd are not supported anymore.
  +- @cosmjs/tendermint-rpc: The fields `CommitSignature.validatorAddress`,
  + `.timestamp` and `.signature` are now optional. They are unset when
  + `blockIdFlag` is `BlockIdFlag.Absent`. The decoding into `CommitSignature` is
  + only updated for the class `Tendermint34Client`, not for `Client`. Please
  + migrate to the former.
  ## [0.24.0] - 2021-03-11
  