I don't recall this, but it's a good find. I would like to point out that this doesn't say that ALL of the Gerudos were sentenced to death. It just says the criminals of the Gerudo Desert, and, if you recall, there was at least one Gerudo who HATED Ganondorf and she ended up becoming a sage. Who's to say that there aren't other Gerudos like her?
Further than that, the Gerudos are not criminals in their society, only to the Hylians, and considering it was probable that the Gerudos ran the Arbiter's Grounds, I doubt they'd all be executed.