textproc/R-cran-yaml: update to 2.3.8

[uzsolt]

Summary

Changelog: https://cran.r-project.org/web/packages/yaml/ChangeLog

https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=275757

Test Plan

Portlint, portfmt, portclippy are ok.
Poudriere builds are okay on amd64 13.2 and 14.0

[diizzy]

Have you at least build tested so users (ports depending on this one) don't break?

[uzsolt]

In D43882#1001770, @diizzy wrote:

Have you at least build tested so users (ports depending on this one) don't break?

I did "testport -i", I can load the library without error and run "make test" without error.
Should I do something else?

[bofh]

@diizzy This is not plain yaml I think and not too much ports should be dependent upon this.

@uzsolt