test: Quarantine GDN2 THD correctness in dev CI

Signed-off-by: Jingyue Wu <jingyuew@nvidia.com>

Author: wujingyue

tests/unit_tests/ssm/test_gated_delta_net2.py

@@ -24,6 +24,12 @@
 class TestGatedDeltaNet(GatedDeltaNetModuleTestCases):
     """GDN2 module correctness across the original parallel layouts."""
 
+    # Recurring THD stalls in TP1/CP1 and TP2/CP2; see #7742.
+    @pytest.mark.flaky_in_dev
+    def test_gpu_forward_thd_correctness(self):
+        """Keep the shared THD assertions with a GDN2-only development quarantine."""
+        super().test_gpu_forward_thd_correctness()
+
 
 # Intermittent compilation/teardown hangs (#7742).
 @pytest.mark.flaky_in_dev