message: remove stake pool id unused import
diff: @@ -6,9 +6,7 @@ use crate::config::{self, Block0Date, ConfigParam};
  use crate::fee::{FeeAlgorithm, LinearFee};
  use crate::leadership::bft::LeaderId;
  use crate::message::Message;
  -use crate::stake::{
  - CertificateApplyOutput, DelegationError, DelegationState, StakeDistribution, StakePoolId,
  -};
  +use crate::stake::{CertificateApplyOutput, DelegationError, DelegationState, StakeDistribution};
  use crate::transaction::*;
  use crate::value::*;
  use crate::{account, certificate, legacy, setting, stake, utxo};
  