Fix SQL queries on demographics page

pkg/models/demographic/queries.go

@@ -123,6 +123,8 @@ func PeopleStatistics() People {
 				COUNT(*) AS user_count
 			FROM
 				users
+			WHERE users.status = 'active'
+			AND users.certified IS TRUE
 			GROUP BY
 				CASE
 					WHEN DATE_PART('year', AGE(birthdate)) BETWEEN 0 AND 25 THEN '18-25'