Ensure _quarto.yml always has an array when it should

[MiguelRodo]

From this link for the project key:

• Done:
  • render
• Checked:
  • resources (seems fine with a string)
• The serve and preview sub-keys don't seem likely to have any array keys.

From this link for the website key:

From this link for the book key:

From this link for the manuscript key:

TO BE CONSIDERED: are we only using this to set the output-dir? If so, using regex might be A LOT simpler.

Ya, we literally do:

It was written just for this function:

.projr_yml_quarto_set_output_dir <- function(path) {
yml_quarto <- .projr_yml_quarto_get()
yml_quarto[["project"]][["output-dir"]] <- path
.projr_yml_quarto_set(yml_quarto)
}

Then we just try use regex to figure this out. This is going to turn into a buggy nightmater otherwise.