Fixes #37036 - Hide next occurrence unless RL is active

in API

app/views/foreman_tasks/api/recurring_logics/base.json.rabl

@@ -6,4 +6,4 @@ attributes :id, :cron_line, :end_time, :iteration, :task_group_id, :state,
 node(:task_count) { |rl| rl.tasks.count }
 node(:action) { |rl| rl.tasks.first.try(:action) }
 node(:last_occurence) { |rl| rl.last_task&.started_at }
-node(:next_occurence) { |rl| rl.next_task&.start_at }
+node(:next_occurence) { |rl| rl.next_task&.start_at if rl.state == 'active' }