Function stake_for_demo 

pub async fn stake_for_demo(
    config: &Config,
    num_validators: u16,
    num_delegators_per_validator: Option<u64>,
    delegation_config: DelegationConfig,
) -> Result<()>

Register validators, and delegate to themselves for demo purposes.

The environment variables used only for this function but not for the normal staking CLI are loaded directly from the environment.

Account indexes 20+ of the dev mnemonic are used for the validator accounts.