Enable HTTP redirect endpoint on pd.w.org

Per https://meta.trac.wordpress.org/ticket/6673

On the Openverse team we recently observed that the CDN domain used by the photo directory, pd.w.org, does not redirect non-httpsHTTPS HTTPS is an acronym for Hyper Text Transfer Protocol Secure. HTTPS is the secure version of HTTP, the protocol over which data is sent between your browser and the website that you are connected to. The 'S' at the end of HTTPS stands for 'Secure'. It means all communications between your browser and the website are encrypted. This is especially helpful for protecting sensitive data like banking information. traffic to https. In fact, it doesn’t handle non-https traffic at all.

As a best practice, these requests should be handled and redirected to their secure counterparts.

$ curl -I http://pd.w.org/
curl: (52) Empty reply from server

cc @coffee2code @zackkrida

#cdn #photos #prio3