Fix divider in subscription page (#27298) (#27301)

Fix divider in subscription page (#27298) (#27301)

Backport #27298 by @yp05327

divider should always display in subscription page.

Before:

![image](https://github.com/go-gitea/gitea/assets/18380374/5a5c948c-8e45-4faa-827e-a05356f3a714)

![image](https://github.com/go-gitea/gitea/assets/18380374/8f6a6747-5414-45cc-8b4c-aa99ea869038)

After:
(no changes when there's no subscriptions)

![image](https://github.com/go-gitea/gitea/assets/18380374/261faf8d-97e2-4d79-a255-5077a42979d2)

![image](https://github.com/go-gitea/gitea/assets/18380374/fc73c837-2efb-40b2-a8f8-2b5c77c32f3b)

Co-authored-by: yp05327 <576951401@qq.com>
Co-authored-by: techknowlogick <techknowlogick@gitea.com>