message: refactor: remove unused PoolError
diff: @@ -64,14 +64,10 @@ pub enum StagingTxResult {
  pub enum PoolError {
  /// An invalid pool entry caused by underlying tx validation error
  InvalidTx(TransactionError),
  - /// An entry already in the pool
  - AlreadyInPool,
  /// CellStatus Conflict
  Conflict,
  /// Transaction pool is over capacity, can't accept more transactions
  OverCapacity,
  - /// A duplicate output
  - DuplicateOutput,
  /// tx_pool don't accept cellbase-like tx
  Cellbase,
  /// TimeOut
  