[CI][AMD][BugFix] Ensure VLLM_ROCM_USE_AITER is set so test_rocm_aiter_topk.py...

[CI][AMD][BugFix] Ensure VLLM_ROCM_USE_AITER is set so test_rocm_aiter_topk.py can run correctly (#33840)
Signed-off-by: Randall Smith <Randall.Smith@amd.com>

tests/kernels/moe/test_rocm_aiter_topk.py

@@ -10,22 +10,28 @@
 # and the platform is not ROCm.
 
 import importlib.util
+import os
 
 import pytest
 import torch
 
+from vllm.platforms import current_platform
+
+if not current_platform.is_rocm():
+    pytest.skip("This test can only run on ROCm.", allow_module_level=True)
+
+# This environment variable must be set so ops will be registered.
+os.environ["VLLM_ROCM_USE_AITER"] = "1"
+
 # this import statement is needed to ensure the ops are registered
 import vllm.model_executor.layers.fused_moe.rocm_aiter_fused_moe  # noqa: F401
-from vllm.platforms import current_platform
 
 # need to import once to ensure the ops are registered
 # Check if aiter package is installed
 aiter_available = importlib.util.find_spec("aiter") is not None
 
-pytestmark = pytest.mark.skipif(
-    not (current_platform.is_rocm() and aiter_available),
-    reason="AITER ops are only available on ROCm with aiter package installed",
-)
+if not aiter_available:
+    pytest.skip("These tests require AITER to run.", allow_module_level=True)
 
 
 def test_rocm_aiter_biased_grouped_topk_custom_op_registration():