Task API Should Allow for Complete Tasks

### Description of the Issue
Box support "review" and "complete" tasks but this SDK only exposes the "review" task as shown [here] (https://github.com/box/box-windows-sdk-v2/blob/5800ee9aa621493d6d23d8628b2bf5b20057309a/Box.V2/Models/Request/BoxTaskCreateRequest.cs#L24)

### Expected Behavior
The SDK should support both task types.

https://developer.box.com/reference/post-tasks/

### Versions Used
.Net SDK: v3.24.0

Start in Box.V2/Models/Request/BoxTaskCreateRequest.cs at the referenced line and compare its task-type support with the Box POST /tasks API documentation. Done means the SDK can represent and send both review and complete task types; verify the request behavior with the project's relevant tests if available.

Written by the indexing model from the issue text.