Get Project Issue Type Hierarchy

Get the issue type hierarchy for a next-gen project.The issue type hierarchy for a project consists of: * *Epic* at level 1 (optional). * One or more issue types at level 0 such as *Story*, *Task*, or *Bug*. Where the issue type *Epic* is defined, these issue types are used to break down the content of an epic. * *Subtask* at level -1 (optional). This issue type enables level 0 issue types to be broken down into components. Issues based on a level -1 issue type must...