Fix pagination with pystac-client >= 0.7.4

[Ariana-B]

Pystac-client 0.7.4 removed default limit, which exposed an error with our pagination.

• Format collections in link so that it remains a comma-separated list -- otherwise we get duplicate collections keys that TypeConversionDict won't catch
• Have next link method match method of original request, rather than defaulting to GET unless intersects value was specified
• Add title and type to next link

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📚 Documentation preview 📚: https://datacube-explorer--578.org.readthedocs.build/en/578/

[robbibt]

Thanks so much @Ariana-B! Can you let me know when this has been rolled out so I can test this out on a range of typical STAC queries?