update cheat sheet link (#4585)

Fix #4591

Author: averiperny

README.Rmd

@@ -38,7 +38,7 @@ devtools::install_github("tidyverse/ggplot2")
 
 ## Cheatsheet
 
-<a href="https://github.com/rstudio/cheatsheets/blob/master/data-visualization-2.1.pdf"><img src="https://raw.githubusercontent.com/rstudio/cheatsheets/master/pngs/thumbnails/data-visualization-cheatsheet-thumbs.png" width="630" height="252"/></a>  
+<a href="https://github.com/rstudio/cheatsheets/blob/master/data-visualization.pdf"><img src="https://raw.githubusercontent.com/rstudio/cheatsheets/master/pngs/thumbnails/data-visualization-cheatsheet-thumbs.png" width="630" height="252"/></a>  
 
 ## Usage
 

README.md

@@ -33,7 +33,7 @@ devtools::install_github("tidyverse/ggplot2")
 
 ## Cheatsheet
 
-<a href="https://github.com/rstudio/cheatsheets/blob/master/data-visualization-2.1.pdf"><img src="https://raw.githubusercontent.com/rstudio/cheatsheets/master/pngs/thumbnails/data-visualization-cheatsheet-thumbs.png" width="630" height="252"/></a>
+<a href="https://github.com/rstudio/cheatsheets/blob/master/data-visualization.pdf"><img src="https://raw.githubusercontent.com/rstudio/cheatsheets/master/pngs/thumbnails/data-visualization-cheatsheet-thumbs.png" width="630" height="252"/></a>
 
 ## Usage