gs-overview-page: Restrict number of curated apps results

The curated apps query can accurately represent all the filtering which
needs to happen to the results list, so the max-results for the query
doesn’t need to exceed the number of curated app tiles we want to show.

Signed-off-by: Philip Withnall <pwithnall@endlessos.org>
3 jobs for query-cleanups in 2 minutes and 50 seconds