[ROCm] Tweak the benchmark script to run on ROCm

[huydhn]

This is a minor tweak to the benchmark script to be able to run it on ROCm

Testing

I'm running the script locally on my ROCm devgpu with the following command HF_TOKEN=<REDACTED> ENGINE_VERSION=v1 bash .buildkite/nightly-benchmarks/scripts/run-performance-benchmarks.sh

cc @houseroad @ywang96

[github-actions]

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[hongxiayang]

lgtm

[huydhn]

Ping for review @ywang96