update nginx log format

Signed-off-by: Basil Bruhn <basil.bruhn@psi.ch>

nginx.conf

@@ -17,8 +17,11 @@ http {
     add_header Referrer-Policy no-referrer-when-downgrade;  # Referrer policy
 
     log_format  main  '$remote_addr - $remote_user [$time_local] "$request" '
-                      '$status $body_bytes_sent "$http_referer" '
-                      '"$http_user_agent" "$http_x_forwarded_for"';
+                    '$status $body_bytes_sent "$http_referer" '
+                    '"$http_user_agent" "$http_x_forwarded_for" '
+                    'proxy_host="$proxy_host" upstream="$upstream_addr" '
+                    'upstream_status="$upstream_status" '
+                    'upstream_time="$upstream_response_time"';
 
     access_log  /var/log/nginx/access.log  main;