Terminal window does not send heartbeat (?)

[ksshannon]

During the SC bash tutorial, it's common to have only a shell open. The terminal doesn't appear to use the jupyter heartbeat or execution API. This causes containers that are only running the terminal to expire and be reclaimed by the system.

This happened to @matty-jones during a workshop. I watched a handful of containers expire, and Matty's was one of them. It clearly should still be alive.

There is no obvious solution, since we rely on the jupyter execution to keep our containers alive.

/cc @mikemhenry

[ksshannon]

Commit 8ab67b3 is a first hack. I believe that there is a much simpler solution, but this is a starting point.