Can only have one: config

Brief description of the problem:
In the subplot function, if I input a mix of ggplot2 object and plotly object, I got 'Warning message: Can only have one: config'. How to fix the warning?
Below is an example.

library(plotly); library(ggplot2)
g <- ggplot(diamonds, aes(x=carat, y=price, color=cut)) + geom_point()
p <- plot_ly(z = volcano, type = "heatmap")
subplot(ggplotly(g), plot_ly(type="heatmap"), p, nrows=2, shareX=TRUE, shareY=TRUE)  

首先使用 ggplot2 和 plotly 运行提供的 R 示例，然后跟踪混合 ggplotly 和 plotly 对象的 subplot 处理。payload 没有指定实现文件或测试；完成意味着确定并处理“Can only have one: config”警告的来源，同时不破坏所示的 subplot 情况。