message: Add CHANGELOG entry for abs_diff
diff: @@ -9,6 +9,10 @@ and this project adheres to
  ### Added
  - cosmwasm-std: Add `Uint{64,128,256,512}::one`.
  +- cosmwasm-std: Add `Uint{64,128,256,512}::abs_diff` and
  + `Decimal{,256}::abs_diff` ([#1334]).
  +
  +[#1334]: https://github.com/CosmWasm/cosmwasm/pull/1334
  ## [1.0.0] - 2022-05-14
  