Twenty Sixteen: Media attachment page displays the image as a site logo if no logo is set

### Impacted plugin

Jetpack

### Steps to Reproduce

1. Activate Twenty Sixteen on a Simple site.
2. Navigate to the Media (`/wp-admin/upload.php`)
3. Click on an image and then click the View attachment page
4. Wait for the attachment page to open.

### A clear and concise description of what you expected to happen.

If you visit an image attachment page on Twenty Sixteen, the image itself shows up as the Site Logo at the top left, even when there are no Site Logos set on the site.

#### What you expected to happen

The attachment page opens with the header/site logo area unaffected.

### What actually happened

The image attachment page opens, but the image shows up as a site logo at the top.

### Other information

Originally reported: https://github.com/Automattic/themes/issues/4786

### Operating System

_No response_

### OS Version

_No response_

### Browser

Chrome/Chromium

### Browser Version(s)

_No response_