Deploy to Shinyapps.io from Github Actions

Last week I spend a few hours figuring out how to auto deploy a shiny app on 2 apps on shinyapps.io from github. You can see the result on this github repository. This github repository is connected to two shiny apps on shinyapps.io. Here is what I envisioned, every new commit to the main branch will be published to the main app. We could then lock down the main branch so that no one can directly commit to main.