CORS blocks cert issuance

To enable CORS on the site there needs to be a file on the `nginx-proxy` container at `/etc/nginx/vhost.d/api.`. Unfortunately that is where the Let'sEncrypt challenge certificate goes with the same name. Now this has only happened once, but if for whatever reason the API server isn't being issued a certificate, this can be temporarily solved by going to the directory, deleting the file with the CORS configuration, and allowing Let'sEncrypt to create its challenge file.

Recommended solution: find a way to put the CORS config on the container long after the challenge cert has been found by LE.