UI should display tale starting spinner during restart

[craig-willis]

Problem
When restarting a tale, the interactive session/IDE can no longer connect to the remote container, displaying various errors. Ideally we would hide the IDE and display some indicator during restart like we do during start.

To repeat

• Create and start a Jupyter tale
• Create apt.txt with contents vim
• Rebuild tale
• While on interactive tab restart tale

Expected results
UI displays tale starting spinner

Actual results
UI displays IDE which can no longer connect to remote container resulting in various errors/warnings (e.g., Directory not found "")

[bodom0015]

Is there an InstanceStatus change when restarting? If the current restart logic already sets the state back to Launching, I would think that the existing logic should handle this case already.

If not, aside from possibly watching for updates coming through the SyncService I'm not sure how to detect if the restart has completed? We could consider adding logic that uses the Launching + Running states to indicate restart, or add a new explicit state for InstanceStatus.RESTARTING

[craig-willis]

Good catch. It looks like the update_container task doesn't change the instance status. I'll look into fixing this in girder_wholetale or gwvolman.