sound: Add tooltips to all speaker test buttons
requested to merge automerisnaranja/gnome-control-center:sound-test-speaker-buttons-tooltips into main
With this change, Orca now reads the word "speaker", for example: "Front Left Speaker push button" instead of "Front Left push button".
Also, remove the a11y labels because Orca also reads tooltips.
Edited by Automeris naranja