[CI/Build][AMD] Fix import errors in tests/kernels/attention (#29032)

Signed-off-by: Randall Smith <ransmith@amd.com>
Co-authored-by: Randall Smith <ransmith@amd.com>

tests/kernels/attention/test_flashinfer_trtllm_attention.py

@@ -1,7 +1,6 @@
 # SPDX-License-Identifier: Apache-2.0
 # SPDX-FileCopyrightText: Copyright contributors to the vLLM project
 
-import flashinfer
 import pytest
 import torch
 
@@ -16,6 +15,8 @@ if not current_platform.is_device_capability(100):
     pytest.skip(
         "This TRTLLM kernel requires NVIDIA Blackwell.", allow_module_level=True
     )
+else:
+    import flashinfer
 
 FLOAT32_BYTES = torch.finfo(torch.float).bits // 8
 FP8_DTYPE = current_platform.fp8_dtype()