Remove "Edit Site" from docs sites

[dd32]

Describe the bug

Similar to WordPress/wporg-main-2022#390 the Documentation site is edited via page contents.

While looking at how to edit older pages such as https://wordpress.org/documentation/wordpress-version/version-2-7/ I noticed that the Edit Site link is there and potentially confusing.

For sites where editors edit content in WordPress, I feel we should enforce the page editor for such things, and as such, hide the Edit Site button unless that's what they're actually after.