code: protected <R> ResultWithNofifications<R, BE> inTxWithNotifications(TransactionPayload<R, BE> payload) {
          return inCommittableTxWithNotifications(context, TransactionPayload.Committing.committing(payload));
      }
docs: Identical to {@link #inTx(TransactionPayload)} but also returns the notifications emitted from the transaction.
  The list of notifications is final and they have already been sent. The caller should NOT send them again.
  
  @param payload the payload to run within a transaction
  @param <R> the type of the result returned from the payload
  @return the result of the payload together with the notifications sent as a result of the transaction