Update layers.md

[shinriyo]

https://www.openstreetmap.org/

• [o ] Update tests
• [o ] Update docs

[ImreSamu]

In my opinion, there's a typo in the new link. It doesn't work for me. The link is: --> https://www.openstreetmap.www.openstreetmap.org/

• "www.openstreetmap.www.openstreetmap.org’s server IP address could not be found."

[nvkelso]

Fixed (again) via https://github.com/tilezen/vector-datasource/pull/2118.