[Fix] Fix gemma CI test failing on main (#20124)

Signed-off-by: Thomas Parnell <tpa@zurich.ibm.com>

tests/models/language/generation/test_gemma.py

@@ -7,14 +7,21 @@ MODELS = ["google/gemma-2b", "google/gemma-2-2b", "google/gemma-3-4b-it"]
 
 
 @pytest.mark.parametrize("model", MODELS)
-def test_dummy_loader(vllm_runner, model: str) -> None:
+def test_dummy_loader(vllm_runner, monkeypatch, model: str) -> None:
+    with monkeypatch.context() as m:
+        m.setenv("VLLM_ALLOW_INSECURE_SERIALIZATION", "1")
         with vllm_runner(
                 model,
                 load_format="dummy",
         ) as llm:
-        normalizers = llm.collective_rpc(lambda self: self.worker.model_runner.
-                                         model.model.normalizer.cpu().item())
-        assert np.allclose(
-            normalizers,
-            llm.llm_engine.model_config.hf_config.hidden_size**0.5,
-            rtol=1e-3)
+            if model == "google/gemma-3-4b-it":
+                normalizers = llm.model.collective_rpc(
+                    lambda self: self.model_runner.model.language_model.model.
+                    normalizer.cpu().item())
+                config = llm.model.llm_engine.model_config.hf_config.text_config
+            else:
+                normalizers = llm.model.collective_rpc(
+                    lambda self: self.model_runner.model.model.normalizer.cpu(
+                    ).item())
+                config = llm.model.llm_engine.model_config.hf_config
+            assert np.allclose(normalizers, config.hidden_size**0.5, rtol=2e-3)