Ensure all cw20 sends use Binary not Option<Binary>

[ethanfrey]

ex: https://github.com/CosmWasm/cosmwasm-plus/blob/main/packages/cw20/src/msg.rs#L16

This was updated in cw20-base, but I forgot the cw20 spec. Let's check all usage in all packages and ensure they match

[pronvis]

Even inside cw20 messages differ :)
cw20-0.6.1/src/receiver.rs:

pub struct Cw20ReceiveMsg {
    pub sender: String,
    pub amount: Uint128,
    pub msg: Binary,
}

cw20-0.6.1/src/msg.rs:

    Send {
        contract: String,
        amount: Uint128,
        msg: Option<Binary>,
    },