Prevent a query to be scheduled on an expired HComb #2
Description
The HComb container is expired every X seconds (currently 120s). It might happen that a Fuse picks up an HComb that is still running when it lists existing tasks, but by the time it calls its API, the HComb is shutdown. In that case the query would fail.
This might be addressed by #3 because using DynamoDB as resource interface would allow better transactionality.