Fix formatting for benchmarks/opsd benchmark scripts
- Add SPDX-License-Identifier and DeepSpeed Team headers to
bench_14b_rollout.py, bench_autotp_gc.py, bench_vllm_tp2.py
- Remove unused 'sys' import from bench_14b_rollout.py (flake8 F401)
- Apply yapf formatting (column_limit=119)
- Add #ignore-cuda comments to torch.cuda.* calls in benchmark scripts
(these are CUDA-specific benchmarks)
Signed-off-by: GitHub <noreply@github.com>