resolve: change phab ongoing incidents to in progress

Prior to this change we listed all 'Open' phab tasks, but this created a problem with old tasks that have never been closed, or tasks that are no longer ongoing, but still are open for followup work.

After:

1. Create task with status 'In Progress'
2. List returns only 'In Progress' tasks
3. Resolving a task moves it to 'Open' and adds a comment indicating the rationale.