[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/kernels/test_machete_mm.py

+# SPDX-License-Identifier: Apache-2.0
 """Tests for the machete kernel.
 
 Run `pytest tests/kernels/test_machete_mm.py`.

tests/kernels/test_mamba_ssm.py

+# SPDX-License-Identifier: Apache-2.0
+
 import pytest
 import torch
 import torch.nn.functional as F

tests/kernels/test_marlin_gemm.py

+# SPDX-License-Identifier: Apache-2.0
 """Tests for the marlin kernel.
 
 Run `pytest tests/kernels/marlin/test_marlin_gemm.py`.

tests/kernels/test_mha_attn.py

+# SPDX-License-Identifier: Apache-2.0
 """
 Test:
 

tests/kernels/test_moe.py

+# SPDX-License-Identifier: Apache-2.0
 """Tests for the MOE layers.
 
 Run `pytest tests/kernels/test_moe.py`.

tests/kernels/test_permute_cols.py

+# SPDX-License-Identifier: Apache-2.0
+
 import pytest
 import torch
 

tests/kernels/test_pos_encoding.py

+# SPDX-License-Identifier: Apache-2.0
+
 from itertools import accumulate, product
 from typing import Dict, List, Optional
 

tests/kernels/test_prefix_prefill.py

+# SPDX-License-Identifier: Apache-2.0
+
 import math
 import random
 import time

tests/kernels/test_rotary_embedding.py

+# SPDX-License-Identifier: Apache-2.0
 """
 Tests for miscellaneous utilities
 """

tests/kernels/test_triton_decode_attention.py

+# SPDX-License-Identifier: Apache-2.0
+
 import pytest
 import torch
 

tests/kernels/test_triton_scaled_mm.py

+# SPDX-License-Identifier: Apache-2.0
 """Tests for the triton_scaled_mm kernel
 
 Run `pytest tests/kernels/test_triton_scaled_mm.py`.

tests/kernels/test_utils.py

+# SPDX-License-Identifier: Apache-2.0
 """
 Tests for miscellaneous utilities
 """

tests/kernels/utils.py

+# SPDX-License-Identifier: Apache-2.0
 """Kernel test utils"""
 
 import itertools

tests/kv_transfer/disagg_test.py

+# SPDX-License-Identifier: Apache-2.0
+
 import os
 import subprocess
 import sys

tests/kv_transfer/module_test.py

+# SPDX-License-Identifier: Apache-2.0
+
 import subprocess
 import sys
 

tests/kv_transfer/test_lookup_buffer.py

+# SPDX-License-Identifier: Apache-2.0
+
 import os
 import random
 

tests/kv_transfer/test_send_recv.py

+# SPDX-License-Identifier: Apache-2.0
+
 import os
 import time
 from typing import List

tests/lora/conftest.py

+# SPDX-License-Identifier: Apache-2.0
+
 import tempfile
 from collections import OrderedDict
 from typing import Dict, List, TypedDict

tests/lora/data/long_context_test_data.py

+# SPDX-License-Identifier: Apache-2.0
+
 # ruff: noqa
 """This file contains a dictionary of prompts and golden responses."""
 

tests/lora/test_baichuan.py

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