Add More Tests to improve Code Coverage

[rstyd]

We need to improve BEE's code coverage. I think the best approach is to do this module by module. For now, let's focus on:

• [ ] Workflow Manager
• [ ] Task Manager
• [ ] Client
• [ ] Container runtime driver

[pagrubel]

Make a new issue for each of the above as you work on it. They should probably be separate PR's.