build_site() should accept absolute paths as build_rmd value

[maelle]

If one uses an absolute path as build_rmd value when calling build_site(), this line

https://github.com/rstudio/blogdown/blob/904b48bf79f3e4fd1f1bfe83dc89f55728ff0d49/R/render.R#L130

makes blogdown believe the file is outside the content directory.

blogdown:::rel_path(blogdown:::content_file())
# "content"
xfun::is_sub_path(
  "~/Documents/ropensci/WEBSITE/roweb3/content/blog/2022-08-02-working-with-qualtrics-data-importing/index.Rmd",
  "content"
)
# FALSE

Checklist

When filing a bug report, please check the boxes below to confirm that you have provided us with the information we need. Have you:

• [x] formatted your issue so it is easier for us to read?

• [x] used blogdown::check_site() function to diagnose your site and corrected potential problems?

• [x] included a minimal, self-contained, and reproducible example?

• [ ] pasted the output from xfun::session_info('blogdown') in your issue?

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[yihui]

Should be fixed now. Thanks for the suggestion!

[maelle]

Thank you! :rocket: