message: Remove obsolete from_address from migration guide
diff: @@ -156,14 +156,12 @@ major releases of `cosmwasm`. Note that you can also view the
  // release counter_offer to creator
  let mut ctx = Context::new();
  ctx.add_message(BankMsg::Send {
  - from_address: env.contract.address.clone(),
  to_address: state.creator,
  amount: state.counter_offer,
  });
  // release collateral to sender
  ctx.add_message(BankMsg::Send {
  - from_address: env.contract.address,
  to_address: state.owner,
  amount: state.collateral,
  });
  @@ -182,14 +180,12 @@ major releases of `cosmwasm`. Note that you can also view the
  // release counter_offer to creator
  let mut resp = HandleResponse::new();
  resp.add_message(BankMsg::Send {
  - from_address: env.contract.address.clone(),
  to_address: state.creator,
  amount: state.counter_offer,
  });
  // release collateral to sender
  resp.add_message(BankMsg::Send {
  - from_address: env.contract.address,
  to_address: state.owner,
  amount: state.collateral,
  });
  