Grafana调整等待时间，避免Gateway timeout报错

使用Grafana的HTTP时，有些即时数据需要运算量与时间，而grafana的默认timeout是30秒，因此需要通过修改配置文件，避免grafana提前中断连接

修改原始配置文件:

1. 删除;
2. 调整timeout=30为timeout=60

# This setting also applies to core backend HTTP data sources where query requests use an HTTP client with timeout set.
;timeout = 30

改为：

# This setting also applies to core backend HTTP data sources where query requests use an HTTP client with timeout set.
timeout = 60