Filter active processes for the default user when running verdi process repair

[edan-bainglass]

This PR applies a filter on the active processes picked up by verdi process repair. The command takes the difference between the set of active processes and queued processes and adds the difference to the broker queue. However, in recent developments of a shared AiiDA setup, the database table of queued jobs (DbQueue) may hold jobs from different profiles (multiple profiles share the database). The broker should not pick up jobs from a profile different from the default user. Here, I apply this exact filter on active jobs (if process.user.is_default). This ensures that the broker does not pick up jobs from any other profile attached to the database.

I don't believe this breaks anything, as there should be no other user with active processes. Here, by active I mean jobs which the broker should correctly attempt to repair. I believe the concept of User in AiiDA was mostly to differentiate imported processes and data. But these processes should not be active (e.g. running, waiting). So the filter in the end makes no difference for single-profile-use database use cases.

[superstar54]

I suggest adding the following cli options.

@options.ALL_USERS(help='Filter to repair processes for all users')
@options.USER(help='Filter to repair processes belonging to a specific user.')

And use the current user if neither is provided.

This will function the same as your current implementation, but also give flexibility for users, in the case the users create multiple "User" in the same profile (a scenario that is allowed, though not documented or encouraged).

[unkcpz]

Suggested change

	active_processes = [process.pk for process in get_active_processes() if process.user.is_default]
	active_processes = (process.pk for process in get_active_processes() if process.user.is_default)

the process will be evaluated and the list can be large, use iterator instead.

[edan-bainglass]

Sorry, haven't had a chance to get back to this. The thing is, somehow in the tests, process is evaluated as an int. Unclear why. Also, maybe best to modify the active process query to optionally filter by the default user, so this list comprehension filtering could be avoided all together. Will think about this later this week.