Private database page should show padlock on every table

Following:
- #1829

https://latest.datasette.io/_internal looks like this:

<img width="741" alt="image" src="https://user-images.githubusercontent.com/9599/197436797-815ab54f-33d9-4f49-981f-628ce4e9013c.png">

But those queries and tables are private too, and should also show the padlock icon.