Dealing with quarto dependencies

[b-rodrigues]

If the R quarto package is listed, the quarto program should be automatically added, and probably pandoc as well.

[b-rodrigues]

this should solve the issue: c3a76bff9109cf2cdd3e98d97fe2e6aa44ea17e4

but I'd be better to add an explicit unit test, for now, the tests for rix test this as well as "quarto" is listed in r_pkgs but not system_pkgs and it works

[b-rodrigues]

So the tests all pass on my main computer, but not on my rpi5 and not on GitHub actions. Wonder what is going on... But I do have an error message, it just gets ignored?

### Start evaluating `expr` in `nix-shell` ###
* wrote R script evaluated via `Rscript` in `nix-shell`: /run/user/1000/RtmpA6heMo/with_nix_r.R

* using Nix with R version 3.5.3 

* called `expr` with args :

* The type of the output object returned by `expr` is integer
* Saved output to /run/user/1000/RtmpA6heMo/_out.Rds

* the following objects are in the global environment:
args_vec current_paths globals i lst message_type new_paths pkgs r_version_num rnix_out temp_dir user_dir userlib_paths

* `sessionInfo()` output:
Error in system(paste(which, shQuote(names[i])), intern = TRUE, ignore.stderr = TRUE) : 
  error in running command
Calls: cat ... withVisible -> eval -> eval -> sessionInfo -> Sys.which
Execution halted

### Finished code evaluation in `nix-shell` ###

* Evaluating `expr` in `nix-shell` returns:
[1] 2 6 5 8 9
✔ |         12 | find_rev [16.4s]
⠏ |          0 | tar_nix_ga                                                           GitHub Actions workflow file save to: /run/user/1000/RtmpA6heMo
✔ |          1 | tar_nix_ga

══ Results ═══════════════════════════════════════════════════════════════════════════
Duration: 16.5 s

[ FAIL 0 | WARN 0 | SKIP 0 | PASS 15 ]

here's the error:

* `sessionInfo()` output:
Error in system(paste(which, shQuote(names[i])), intern = TRUE, ignore.stderr = TRUE) : 
  error in running command
Calls: cat ... withVisible -> eval -> eval -> sessionInfo -> Sys.which
Execution halted

could that be the reason?