Recently used zhashx_dup() to copy a hash, leading to an assert in zhashx_insert() while in the middle of the copy iteration in zhashx_dup().

Eventually, I determined the issue was that we use an alternate setting of the key hasher, comparator, duplicator, and destructor. However in zhashx_dup() it does not appear to copy those over. It only copies over the item duplicator/destructor.

    zhashx_t *copy = zhashx_new ();
    if (copy) {
        copy->destructor = self->destructor;
        copy->duplicator = self->duplicator;

I think it should be using the same hasher/key functions across the board?