[CI] Lower GSM8K baselines for B200 nightly after eval unification#22136

Kangyan-Zhou wants to merge 2 commits intosgl-project:mainsgl-project/sglang:mainfrom

Kangyan-Zhou:fix_nightly_b200_accuracyKangyan-Zhou/sglang:fix_nightly_b200_accuracyCopy head branch name to clipboard