GET /topic/%23%E3%83%9E%E3%83%AA%E3%83%8E%E3%82%B9%E3%82%B1%EF%BC%AA%E3%83%9E%E3%82%B9%E3%82%B3%E3%83%83%E3%83%88%E7%B7%8F%E9%81%B8%E6%8C%99