[REQUEST] escalate privileges to kill processes

[Atemu]

Is your feature request related to a problem? Please describe.
A clear and concise description of what the problem is. Ex. I'm always frustrated when [...]

Sometimes you need to kill a privileged process or the process of another user but that is not possible when running btop as a regular user (as one does).

Describe the solution you'd like
A clear and concise description of what you want to happen.

Btop should open a privilege escalation prompt using polkit and/or sudo when attempting to kill a process that the user is not permitted to kill.

Describe alternatives you've considered
A clear and concise description of any alternative solutions or features you've considered.

Additional context
Add any other context or screenshots about the feature request here.