Add setting to hide label when the battery is fully charged

After I upgraded from Fedora 41 to 42, XFCE Power Manager has started to misbehave.

Now it shows that my battery is being charged and the 0:00 remaining time when nothing like that is happening.

I'm using xfce4-power-manager-4.20.0-2.fc42.x86_64

That wasn't an issue with the previous release.

My battery does NOT charge to 100%, it's configured to charge only to 80% in the EFI settings.

Anyway, acpi -V returns:

acpi -V
Battery 0: Full, 100%
Battery 0: design capacity 4145 mAh, last full capacity 3316 mAh = 80%

This is a regression/bug.