Relaunch scenario without saved progress

[pi-unnerup]

As a user I want to be able to relaunch a scenario I have already started without keeping the scenario progress. This allows me to complete a scenario several times or restart a scenario I think I might have messed up.
Currently the scenario progress is saved in progress.yaml and does not get overridden, even if the infrastructure is torn down and scenario is restarted

Expected behaviour
simulator scenario launch <scenario name> always resets the progress for that scenario, so I can restart a task.

Actual behaviour
simulator scenario launch <scenario name> followed by start_task 1 informs me I am already on task 1 if I have started this task before.

[s-irvine]

It may be worth adding a simulator scenario reset command for this purpose. If someone has to tear down their infra they want to continue a scenario from where they were when they spin it back up.