clean up R CMD CHECK workflow

[nickreich]

• remove extraneous package installs that confuses new users who don't have all packages installed (e.g. DT)
• actually check the vignettes if possible

[bsweger]

@nickreich there's a render vignette step in the test action: https://github.com/reichlab/covidHubUtils/blob/master/.github/workflows/pr_unittest.yaml#L86

It uses the rmarkdown::render("vignettes/covidHubUtils-overview.Rmd") incantation, which looks like it executes the .Rmd code.

This may explain the --no-vignettes we see in the R CMD CHECK workflow.

Will this suffice for the second checkbox in the short term?

In the longer term, I'm going to create an issue to bring this repo's R CMD CHECK workflow in line with the corresponding workflows over in the hubverse, which make use of tools like r-lib/actions/check-r-package@v2 (for example)

Edit to add: I'm proposing the short term here so I can fast-track the local dev setup and work on the actual bug I'm assigned to 😅

[nickreich]

I created the other issue just so we didn't lose it, and yes, I think for the short-term this should work. Let's get back to the assigned bug!

[bsweger]

Closing, as this was resolved in #409 (I used the wrong wording to auto link the ticket)