When using the previous approach I've always gotten errors that I can't
reload config on the .lock file that exists in /tmp when you run a
standard configured hyprland.
This commit improves this by using hyprctl to find instances to reload
instead.
We can remove the HYPRLAND_INSTANCE_SIGNATURE bogus assignment once
https://github.com/hyprwm/Hyprland/issues/4088 is resolved.
Co-authored-by: Carl Hjerpe <git@hjerpe.xyz>
7a88cdedbd