Execute a transaction that involves consensus pool management, like
        adding a node, client or a steward.

        :param ppTime: PrePrepare request time
        :param reqs_keys: requests keys to be committed

def execute_pool_txns(self, three_pc_batch) -> List:
        """
        Execute a transaction that involves consensus pool management, like
        adding a node, client or a steward.

        :param ppTime: PrePrepare request time
        :param reqs_keys: requests keys to be committed
        """
        committed_txns = self.default_executer(three_pc_batch)
        for txn in committed_txns:
            self.poolManager.onPoolMembershipChange(txn)
        return committed_txns