Update swh-search QL examples

09:29:03 <+zack> as a minor doc/ux point, most of the example queries in the doc return no results right now, which makes people believe the search is not working 09:29:09 <+zack> (which I believe is not actually the case) 09:29:21 <+zack> we should replace them with both meaningful and successful queries i believe

09:41:05 <+douardda> vlorentz: BTW the doc gives 2 examples with ':' as operator instead of '=' (like 'metadata : "and"')

https://docs.softwareheritage.org/devel/swh-search/query-language.html

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Migrated from T3930 (view on Phabricator)