[Bugfix] Avoid racy accepted counts in async spec decode (#45100)
Signed-off-by: Weiwei Sun <68775773+sunnweiwei@users.noreply.github.com>
Co-authored-by: mergify[bot] <37929162+mergify[bot]@users.noreply.github.com>
Co-authored-by: Jiangyun Zhu <riverclouds.zhu@qq.com>
