Support changing the task that gets run via ssh

[fhunleth]

This would be helpful for supporting advance tasks that aren't upgrades. Examples include pushing the ops.fw firmware to do things like validate partitions, erasing the data partition, or updating U-Boot environment variables with fwup. Another option is to run the complete task which while it isn't recommend, can be nice to try to see if you get lucky before removing MicroSD cards, etc.

[fhunleth]

I need to think about this use case a bit more. I keep on thinking of easier ways to accomplish what I originally wrote. I think that the linked PR that Copilot made is a decent way of supporting this if there is, indeed, a reason to add the feature.