Fix banning players by name

[P3ridot]

So without this missing method, server uses default JsonList#a method implementation which returns just toString for key (in this case it's GameProfile). By adding this method, we return result of GameProfileBanList#b which looks like that

protected String b(GameProfile gameprofile) {
    return gameprofile.getId().toString();
}

It's done in the same way in WhiteList and there everything works

[HanielCota]

That is good! like

[mechoriet]

Seems like this method just got deleted instead of decompile fixed https://github.com/hpfxd/PandaSpigot/blob/master/patches/server/0001-Fix-Decompilation-errors.patch#L621-L632

[uRyanxD]

Yeah