testing/gamescope: enable, update wlroots subproject
gamescope 3.15.14 uses wlroots 18 and therefore is incompatible with the current wlroots used (wlroots 17).
Closes #16649 (closed)
gamescope 3.15.14 uses wlroots 18 and therefore is incompatible with the current wlroots used (wlroots 17).
Closes #16649 (closed)