ci: Disable trace testing on Mali T760

The machine is showing random mis-renderings and we don't have time now
to investigate. Comment it out for now so CI pipelines don't fail due to
it.

Signed-off-by: Tomeu Vizoso <tomeu.vizoso@collabora.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/6023>
1 file changed