Fix Streamlit websocket proxy in nginx

docker/nginx.conf.template

@@ -39,9 +39,13 @@ http {
 
     location / {
       proxy_pass http://127.0.0.1:8501;
+      proxy_http_version 1.1;
+      proxy_set_header Upgrade $http_upgrade;
+      proxy_set_header Connection $connection_upgrade;
       proxy_set_header Host $host;
       proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
       proxy_set_header X-Forwarded-Proto $scheme;
+      proxy_read_timeout 3600;
     }
   }
 }