mesa/tests: add missing dep_thread

Fixes: f8c27c2775 ("state_tracker: Move the format test out to be an actual unit test.")
Signed-off-by: Eric Engestrom <eric.engestrom@intel.com>
Reviewed-by: Eric Anholt <eric@anholt.net>
Tested-by: Vinson Lee <vlee@freedesktop.org>

src/mesa/state_tracker/tests/meson.build

@@ -35,6 +35,7 @@ test(
       libmesa_st_test_common, libmesa_gallium, libglapi, libgallium,
       libmesa_util,
     ],
+    dependencies : dep_thread,
   ),
   suite : ['st_mesa'],
 )