If you include a default empty `data` option in your JSON API response,
many frontend frameworks will ignore your `related` link that could be
used to load relationship records, and will instead treat the
relationship as empty.
This adds a `lazy_load_data` option which will:
* stop the serializer attempting to load the data and;
* exclude the `data` key from the final response
This allows you to lazy load a JSON API relationship.
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