Fix copilot review items

Author: jabenninghoff

R/upkeep.R

@@ -158,7 +158,7 @@ upkeep_checklist <- function(last_upkeep = last_upkeep_year()) {
     ),
     todo(
       "Add alt-text to pictures, plots, etc; see https://posit.co/blog/knitr-fig-alt/ for \\
-      examples and https://posit.co/blog/knitr-fig-alt/ for additional guidance."
+      examples and https://pkgdown.r-lib.org/articles/accessibility.html for additional guidance."
     ),
     ""
   )

vignettes/rdev.Rmd

@@ -78,8 +78,8 @@ for markdown) and Vim (which is faster for some types of edits).
 
 Posit is developing a next-generation R and Python IDE based on Visual Studio Code,
 [Positron](https://github.com/posit-dev/positron). While I've tried using Positron, I've found that
-has too many [missing features](https://positron.posit.co/migrate-rstudio-compare.html) to replace
-RStudio for my development, including:
+it has too many [missing features](https://positron.posit.co/migrate-rstudio-compare.html) to
+replace RStudio for my development, including:
 
 - Lack of a notebook-style interface for RMarkdown or Quarto documents
 - No support for lintr