devel/R-cran-systemfonts: Update to 1.3.1
- Use custom do-test because the cran.mk's --no-build-vignettes causes error
- Mark tests as safe
- Install svglite in pre-test, since it doesn't have a port yet
ChangeLog: https://github.com/r-lib/systemfonts/releases/tag/v1.3.1
PR: 289931