[Misc] Add SPDX-License-Identifier headers to python source files (#12628)

- **Add SPDX license headers to python source files**
- **Check for SPDX headers using pre-commit**

commit 9d7ef44c3cfb72ca4c32e1c677d99259d10d4745
Author: Russell Bryant <rbryant@redhat.com>
Date:   Fri Jan 31 14:18:24 2025 -0500

    Add SPDX license headers to python source files
    
This commit adds SPDX license headers to python source files as
recommended to
the project by the Linux Foundation. These headers provide a concise way
that is
both human and machine readable for communicating license information
for each
source file. It helps avoid any ambiguity about the license of the code
and can
    also be easily used by tools to help manage license compliance.
    
The Linux Foundation runs license scans against the codebase to help
ensure
    we are in compliance with the licenses of the code we use, including
dependencies. Having these headers in place helps that tool do its job.
    
    More information can be found on ...

tests/mq_llm_engine/test_abort.py

+# SPDX-License-Identifier: Apache-2.0
 """Test that aborting is handled properly."""
 
 import asyncio

tests/mq_llm_engine/test_error_handling.py

+# SPDX-License-Identifier: Apache-2.0
 """Test that various errors are handled properly."""
 
 import asyncio

tests/mq_llm_engine/test_load.py

+# SPDX-License-Identifier: Apache-2.0
 """Test that the MQLLMEngine is able to handle 10k concurrent requests."""
 
 import asyncio

tests/mq_llm_engine/utils.py

+# SPDX-License-Identifier: Apache-2.0
+
 import asyncio
 import multiprocessing
 from typing import Callable, Tuple, Union

tests/multi_step/test_correctness_async_llm.py

+# SPDX-License-Identifier: Apache-2.0
+
 # Test the AsyncLLMEngine with multi-step-decoding
 from typing import List, Optional
 

tests/multi_step/test_correctness_llm.py

+# SPDX-License-Identifier: Apache-2.0
+
 # Test the LLMEngine with multi-step-decoding
 
 import copy

tests/multimodal/test_inputs.py

+# SPDX-License-Identifier: Apache-2.0
+
 import torch
 
 from vllm.multimodal.inputs import MultiModalKwargs, NestedTensors

tests/multimodal/test_processing.py

+# SPDX-License-Identifier: Apache-2.0
+
 from contextlib import nullcontext
 from typing import cast
 from unittest.mock import MagicMock

tests/multimodal/test_processor_kwargs.py

+# SPDX-License-Identifier: Apache-2.0
+
 from array import array
 from typing import Callable, Dict, Mapping, Optional
 from unittest.mock import patch

tests/multimodal/test_utils.py

+# SPDX-License-Identifier: Apache-2.0
+
 import base64
 import mimetypes
 import os

tests/multimodal/utils.py

+# SPDX-License-Identifier: Apache-2.0
+
 import numpy as np
 from PIL import Image
 

tests/neuron/test_prefix_prefill.py

+# SPDX-License-Identifier: Apache-2.0
+
 import random
 from typing import Optional
 

tests/plugins/vllm_add_dummy_model/setup.py

+# SPDX-License-Identifier: Apache-2.0
+
 from setuptools import setup
 
 setup(name='vllm_add_dummy_model',

tests/plugins/vllm_add_dummy_model/vllm_add_dummy_model/__init__.py

+# SPDX-License-Identifier: Apache-2.0
+
 from vllm import ModelRegistry
 
 

tests/plugins/vllm_add_dummy_model/vllm_add_dummy_model/my_gemma_embedding.py

+# SPDX-License-Identifier: Apache-2.0
+
 from typing import Iterable, List, Optional, Tuple, Union
 
 import torch

tests/plugins/vllm_add_dummy_model/vllm_add_dummy_model/my_llava.py

+# SPDX-License-Identifier: Apache-2.0
+
 from typing import Optional
 
 import torch

tests/plugins/vllm_add_dummy_model/vllm_add_dummy_model/my_opt.py

+# SPDX-License-Identifier: Apache-2.0
+
 from typing import Optional
 
 import torch

tests/plugins/vllm_add_dummy_platform/setup.py

+# SPDX-License-Identifier: Apache-2.0
+
 from setuptools import setup
 
 setup(

tests/plugins/vllm_add_dummy_platform/vllm_add_dummy_platform/__init__.py

+# SPDX-License-Identifier: Apache-2.0
+
 from typing import Optional
 
 

tests/plugins/vllm_add_dummy_platform/vllm_add_dummy_platform/dummy_attention_backend.py

+# SPDX-License-Identifier: Apache-2.0
+
 from vllm.attention.backends.flash_attn import FlashAttentionBackend