Our other Nginx configs should support `proxy_set_headers` like GitLab does
For GitLab Nginx we are able to set `proxy_set_headers` to make proxy SSL termination possible. ~~The new registry Nginx configuration does not have this same configuration. Please allow registry to use similar configuration so users can terminate SSL at load balancers.~~ **Update:** Registry has been done, but we need to make sure this has been added in all our nginx configs cc/ @marin @twk3
issue