[Perf] Optimize _update_states for GPU model runner

[SnowCharmQ]

This PR makes a small optimization for the _update_states method in v1/worker/gpu_model_runner.py. The change slightly improves the performance while maintaining readability.

[github-actions]

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[mgoin]

Nice find for sort, I wasn't aware of this difference

https://docs.python.org/3/howto/sorting.html#sorting-basics

You can also use the list.sort() method. It modifies the list in-place (and returns None to avoid confusion). Usually it’s less convenient than sorted() - but if you don’t need the original list, it’s slightly more efficient.