Demographics page: count only 'gallery' photos

The photo stats were counting ALL public photos of certified members,
whether featured on the Site Gallery or not. Update the query to filter
for Site Gallery photos instead.

pkg/models/demographic/queries.go

@@ -278,6 +278,7 @@ func PhotoStatistics() Photo {
 			photos
 		JOIN users ON (photos.user_id = users.id)
 		WHERE photos.visibility = 'public'
+		AND photos.gallery IS TRUE
 		AND users.certified IS TRUE
 		AND users.status = 'active'
 		GROUP BY photos.explicit

web/templates/demographics.html

@@ -210,7 +210,7 @@
             {{range .Demographic.People.IterOrientations}}
             <div class="columns">
                 <div class="column is-3">
-                    <strong>{{or .Label "(No answer)"}}</strong>
+                    <strong>{{or .Label "No answer"}}</strong>
                     <small class="has-text-grey">({{FormatNumberCommas .Count}})</small>
                 </div>
                 <div class="column pt-4">