Documentation
This PR updates the documentation to fix an incorrect description for
the Unsplash configuration.
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## Summary by CodeRabbit
- **Documentation**
- Corrected a hyperlink and associated text in the self-hosting
configuration guide, changing "Giphy" to "Unsplash" for image search
references.
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Signed-off-by: Victor Santos <vsantos.py@gmail.com>
619a548fba