players were switching from a weaker tool to a stronger one to get double knockback in PvP.
while it's intended that we don't cancel the second attack during hit cooldown if the damage is
higher (the first damage is subtracted to prevent doubling up), we don't want them to get double
knockback.
this behaviour now matches vanilla to the best of my observations.
Come at me PvP community... I know some people are going to hate this change
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