Change Oolite test to support Wayland native as well as XWayland

[mcarans]

Oolite's test uses xwfb-run which assumes XWayland. It should be changed to try native Wayland and fallback to XWayland to support moving to SDL3. According to AI, this can be done like this:

dbus-run-session -- cage -- ./your-app

On Debian systems, these dependencies are needed:
cage xwayland libwayland-bin dbus-x11

[mcarans]

Looks like this may not be needed - apparently xwfb-run is the correct way to support both. Might need to install cage though and add this to Python if there is an EGL_BAD_ALLOC error:

# This prevents the headless compositor from trying to probe 
# your GPU, which fixes the EGL_BAD_ALLOC error in headless mode.
env["WLR_RENDERER"] = "pixman"