GetSequenceFlowsBetween could return wrong list of flows between tasks in a complex process

### Description of the bug

If there are multiple routes between two tasks GetSequenceFlowsBetween could choose the "wrong" path between tasks.

Example flow
```mermaid
stateDiagram
direction LR
state fork <>
state join <>
[*] --> Task1
Task1 --> fork
fork --> Task2
fork --> join
Task2 --> join
join --> Task3
Task3 --> [*]
```

There is in this scenario a possibility that the wrong path is returned.

### Steps To Reproduce

Not actually verified, bug is created after working on the code

### Additional Information

The method is used to get the FlowType of the SequenceFlow between two tasks and is tied to bug #61

As mentioned in #61: Adding possible state changing code to sequenceflows in a process seems like a bad idea. We should find a solution more in line with BPMN.

Start by locating GetSequenceFlowsBetween and inspect how it selects a route when multiple paths connect the same tasks. Reproduce the diagrammed fork/join case and verify which sequence flows are returned. Review bug #61 and the BPMN-related concerns before defining the expected behavior; done means the selected flow list is deterministic and represents the intended route.

Written by the indexing model from the issue text.