fix: cast the final value to keep the scale

lib/rating/models/rating/rating.rb

@@ -26,7 +26,7 @@ def averager_data(resource, scopeable)
 
         sql = %(
           SELECT
-            CAST(#{total_count} AS DECIMAL(25, 16) / #{distinct_count}) count_avg,
+            CAST(#{total_count} / #{distinct_count} AS DECIMAL(25, 16)) count_avg,
             COALESCE(AVG(value), 0) rating_avg
           FROM #{rate_table_name}
           WHERE