Fix pkgdown/bookdown CI failure by installing remotes in docs workflow

[Copilot]

The pkgdown-and-bookdown Actions job fails while rendering the user manual because bookdown executes devtools::install_local() from inst/bookdown/02-ex-simple.Rmd, which requires remotes at runtime. The workflow currently installs devtools and bookdown but not remotes.

• Root cause

  • bookdown::render_book("inst/bookdown", ...) hits the Insall_Local chunk in inst/bookdown/02-ex-simple.Rmd.
  • That chunk calls devtools::install_local("../..", ...), which errors when remotes is missing.

• Change made

  • Updated .github/workflows/update-deploy-manual-pkgdown.yaml to install remotes in the setup-r-dependencies step for pkgdown-and-bookdown.

• Why this is minimal

  • No package code or manual content changed.
  • Single workflow dependency addition to satisfy existing render-time behavior.

- uses: r-lib/actions/setup-r-dependencies@v2
  with:
    extra-packages: any::pkgdown, local::., any::devtools, any::bookdown, any::remotes
    needs: website

[iantaylor-NOAA]

I thought that remotes was a dependency of devtools, but apparently it was moved to "suggests" 6 months ago: r-lib/devtools@713809d, making this simple change in SSMSE necessary.