Revert "i3: workaround an issue with brightness not up-to-date in polybar"

This reverts commit 9674bbfdde. Use
`use-actual-brightness = true` in polybar configuration instead.

bin/brightness

@@ -1,7 +0,0 @@
-#!/bin/sh
-
-# Set brightness and sleep a bit before reading back the value
-
-brightnessctl -q set $1
-sleep 0.1
-brightnessctl > /dev/null

config

@@ -39,8 +39,8 @@ bindsym XF86AudioPrev        exec --no-startup-id exec playerctl -p $mediaplayer
 bindsym $mod+s exec --no-startup-id exec ~/.config/i3/bin/rofi-mediaplayer $mediaplayer
 
 # brightness
-bindsym XF86MonBrightnessUp   exec --no-startup-id exec ~/.config/i3/bin/brightness 5%+
+bindsym XF86MonBrightnessUp exec --no-startup-id exec brightnessctl -q set +5%
-bindsym XF86MonBrightnessDown exec --no-startup-id exec ~/.config/i3/bin/brightness 5%-
+bindsym XF86MonBrightnessDown exec --no-startup-id exec brightnessctl -q set 5%-
 
 # use Mouse+$mod to drag floating windows to their wanted position
 floating_modifier $mod

dotfiles/polybar.conf

@@ -88,6 +88,7 @@ label = %percentage: 2%%
 ramp-0 = 
 ramp-1 = 
 enable-scroll = true
+use-actual-brightness = true
 
 [module/cpu]
 type = internal/cpu