Set `height` in `ploty_ly` and use `height = "auto"` in `plotlyOutput`

Hello,

In the doc of plotlyOutput, the usage of height="auto" is not encouraged. However using height="auto" in plotlyOutput and setting height in the plot_ly function gives a perfect result, and this is very useful to have the ability to set the height in the plot_ly function. So I think this "trick" should be mentioned in the doc.

定位 plotlyOutput 文档及其当前关于 height="auto" 的说明，然后查看 plot_ly 文档中关于 height 参数的内容。更新文档，说明如何在 plotlyOutput 中使用 height="auto"，同时在 plot_ly 中设置 height，并验证渲染后的文字是否清楚地解释了这种用法。