x11/waybar: update to 0.9.12

Changes: https://github.com/Alexays/Waybar/releases/tag/0.9.11
Changes: https://github.com/Alexays/Waybar/releases/tag/0.9.12
Reported by: GitHub (watch releases)

(cherry picked from commit 9f4fb0777e6c5b25be9bedab80281ea5a1a0ba8c)