[Feature Request] Show current battery charge/discharge rate in battery applet

[CalmSeoul]

It would be really nice to have an option to show the battery's current charge/discharge rate if using cosmic on a laptop. This is the rate that can be seen in the Gnome Vitals extension, or when running btop in a terminal, for example.

[LiamillionSS]

This would be useful to add to the existing request for change time estimate https://github.com/pop-os/cosmic-applets/issues/664