Any user may begin the running of a task, not just the user that submitted it

Possibly a desirable use case ("You queue up a bunch of scans you want to do, and I'll just churn through them while you get lunch") but also possibly undesirable (most(?) of the time, process will be submit task, run task, as exposed through the python cli).

When authentication information is passed as part of submitting a task, it may become necessary to check that the authentication information passed as part of running the task matches the user- but the submitting information may have had to have been refreshed, so cannot just check that it is the same.

## Acceptance Criteria
- Either user1 cannot run a task that has been submitted by user2
- Or situations in which user1 may run a task submitted by user2 have been documented
- Or configuration is available to switch between the two configurations