Machine status icon is ! if new content changes workflow stage names

[mclamb]

Not sure if this is UX or drp.

If a machine is set to a workflow and the workflow content changes (via content pack upload) with different stage names, then the machine icon will be set to "!" presumably because it thinks it can no longer find a given stage name in the workflow. However, the workflow has been updated and does have the correct stage names, so nothing is really in error.