Description of problem:
Taking task export when some task runs a sub-task, the sub-task has "Ended at: " filled by the current time.

"Ended at: " should be empty, though. Since the sub-task hasnt finished yet.


Version-Release number of selected component (if applicable):
Sat6.1.7


How reproducible:
100%


Steps to Reproduce:
1. Kick off some longer task (i.e. sync rhel5-7 base repo)
2. Take task export:
foreman-rake foreman_tasks:export_tasks
3. check the task in task export is still pending, but a sub-task running (like  Actions::Pulp::Consumer::SyncNode for the long sync) has filled "Ended at: " by the current time.


Actual results:
3. "Ended at: " for the sub-task contains time when the task export was running


Expected results:
3. "Ended at: " should be empty for the sub-task being executed / pending.


Additional info: