use https for proxy headers in nginx

proxy_pass http://spot:80;

proxy_set_header Host $http_host;

proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;

proxy_set_header X-Forwarded-Proto $scheme;

proxy_set_header X-Forwarded-Proto https;

proxy_buffering on;

proxy_buffer_size 128k;

proxy_buffers 4 256k;