Fix stop_profile does not wait for finishing

[fzyzcjy]

Motivation

This causes issue in bench_one_batch_sever.py, where the logic is stopping profile and then quiting. Since the original stop_profile is fire-and-forget instead of waiting-for-finishing, the subprocesses gets killed.

Please subtract diff from #4740

EDIT: possibly related #3988, where start_profile does wait

Modifications

Checklist

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[merrymercy]

please fix the conflicts

[fzyzcjy]

done

[fzyzcjy]

conflicts resolved