Now we show not only the collection being linked to, but also the
document title:

Previously this example was just displayed as: `Linked to Users`
- I've added a loading state in case the request is slow (verified with
fake slow connection).
- I have verified that if the `useAsTitle` is not defined, it correctly
fallbacks to the id
Please let me know if the same needs to be done with Slate.
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Co-authored-by: Alessio Gravili <alessio@gravili.de>