[VoiceOver] Notification Settings concerns

<img width="320" alt="iPhone Xs — 12 2 2019-11-08 14-24-48" src="https://user-images.githubusercontent.com/198826/68511601-91bea700-0233-11ea-81b7-d060b15f1206.png">

• [ ] The View All does not have the .button trait. It should also have a hint that it expands the list.
• [ ] The site cells can be joined better by adding “Site Name at Site URL”