Comment 3 for bug 2009734

Thanks! It worked when I set it like this:
```
indico.local:
  haproxy-extra-configs:
        - timeout server 300s
  locations:
    /:
      backend-check-method: GET
      backend-check-path: /health
      backend-inter-time: 10s
      backend-maxconn: 50
      backends: ['192.168.68.57:80']
      backend-options: ['http-request set-header X-Forwarded-For %[src]','timeout server 300s']
      extra-config:
        - client_max_body_size 15m
        - proxy_cache_bypass
        - proxy_read_timeout 300s
```