Backport #25781 by @wxiaoguang
Fix#25627
1. `ctx.Data["Link"]` should use relative URL but not AppURL
2. The `data-params` is incorrect because it doesn't contain "page". JS
can simply use "window.location.search" to construct the AJAX URL
3. The `data-xxx` and `id` in notification_subscriptions.tmpl were
copied&pasted, they don't have affect.
Co-authored-by: wxiaoguang <wxiaoguang@gmail.com>