pub(crate) fn next_tx(
        mut self,
        description: &'static str,
        tx: Transaction,
        result: BatchTransactionExecutionResult,
    ) -> Self {
        self.actions
            .push_back(ScenarioItem::Tx(description, tx, result));
        self
    }
Expect the state keeper to request a transaction from IO.
Adds both a transaction and an outcome of this transaction (that would be returned to the state keeper from the
batch executor).
core/node/state_keeper/src/testonly/test_batch_executor.rs