Add Json binding option to use field names instead of local names

[tefra]

    Hello, is it possible to make this optional? I went to upgrade this dependency in a project that relies on the json output having different key names and afaict it's not possible to make it output `var.name` instead of `var.local_name` without just copying next_value and changing that yield.

Specifically here, https://github.com/tefra/xsdata/blob/v22.11/xsdata/formats/dataclass/serializers/json.py#L104

Originally posted by @delfick in #389 (comment)

[tefra]

Hi @delfick iat that time I was using the json bindings for tests mostly, it doesn't make sense to add an option to override the qualified name. It's pretty easy to override the JsonSerializer to achieve this.

[delfick]

I did end up doing this but it feels hacky to me

# TODO: Hopefully future version of xsdata makes the key behaviour configurable
class ModifiedJsonSerializer(serializers.JsonSerializer):
    def next_value(self, obj: t.Any) -> t.Iterator[t.Tuple[str, t.Any]]:
        """
        Exactly the same as is in serializers.JsonSerializer accept we yield var.name
        instead of var.local_name
        https://github.com/tefra/xsdata/issues/389#issuecomment-1305216183
        """
        ignore_optionals = self.config.ignore_default_attributes

        for var in self.context.build(obj.__class__).get_all_vars():
            value = getattr(obj, var.name)
            if var.is_attribute and ignore_optionals and var.is_optional(value):
                continue

            yield var.name, self.convert(value, var)

and surely this is exactly the kind of thing the config class is for?