fix: gunicorn.conf.py 从 sync 改为 gthread，修复全站卡死根因

Co-authored-by: Cursor <cursoragent@cursor.com>

deploy/systemd/gunicorn-dianjing.service

@@ -7,7 +7,7 @@ Type=simple
 User=root
 Group=root
 WorkingDirectory=/opt/1panel/apps/openresty/nginx/www/sites/43.142.166.152.443/django
-ExecStart=/usr/local/bin/gunicorn --bind 127.0.0.1:8001 --workers 6 --threads 4 --worker-class gthread --timeout 120 --log-level warning --access-logfile /dev/null --error-logfile /tmp/gunicorn-error.log a_long_dianjing.wsgi:application
+ExecStart=/usr/local/bin/gunicorn -c gunicorn.conf.py a_long_dianjing.wsgi:application
 Restart=always
 RestartSec=3
 StandardOutput=null