CI tests for complex scenarios

[greenhat]

Motivation

To test more complex scenarios where outputs from one operation are the inputs to another operation. For example, consider the following scenario:

1. Bootstrap new oracle pool;
2. Invite oracles (send them oracle token + reward token);
3. Invited oracles posting their datapoints;
4. Run refresh command to collect posted datapoints;
5. Repeat steps 3, and 4 one more time.

Manually testing this scenario is a tedious and error-prone job.

Implementation details

Firing up real nodes with attached oracles is a no-go. Let's try to simulate the node's role and the whole UTXO model with a simplified implementation similar to the one we have in https://github.com/ergoplatform/ergo-playgrounds (BlockchainSimulation and Party traits and their implementation)