Update required at docs/cosmwasm/testnet/cosmwasm-deployment.md

rust optimizer version need to updated in the below command to cosmwasm/rust-optimizer:0.17.0 pls:

`
sudo docker run --rm -v "$(pwd)":/code \
    --mount type=volume,source="$(basename "$(pwd)")_cache",target=/code/target \
    --mount type=volume,source=registry_cache,target=/usr/local/cargo/registry \
    cosmwasm/rust-optimizer:0.12.6
`

Thanks