Utilize RStudio Package Manager for Docker Images

[JosiahParry]

dock_from_renv() writes a Dockerfile with cran.rstudio.com as the CRAN repository which does not serve linux binaries. For a better experience, RStudio Package Manager should be added as the default package repo to avoid building packages from source.

dockerfiler/R/dock_from_renv.R

Line 53 in e40f804

repos = c(CRAN = "https://cran.rstudio.com/"),

[JosiahParry]

Note that it is now referred to as Posit Public Package Manager (P3M) and is available at https://p3m.dev/client/#/repos/cran/setup?distribution=ubuntu-22.04. Using CRAN source packages results in exceptionally long build times. Providing a users with an efficient default would be a QOL improvement.