fix rstudio badge

README.md

@@ -9,7 +9,7 @@
 image            | description                               | badges 
 ---------------- | ----------------------------------------  | ------ 
 r-ver            |  Version-stable base R & src build tools  | [![](https://images.microbadger.com/badges/image/rocker/r-ver.svg)](https://microbadger.com/images/rocker/r-ver) [![](https://img.shields.io/badge/Dockerfile-v3.3.2-blue.svg)](https://github.com/rocker-org/rocker-versioned/blob/master/r-ver/3.3.2/Dockerfile)  [![](https://img.shields.io/badge/Dockerfile-latest-blue.svg)](https://github.com/rocker-org/rocker-versioned/blob/master/r-ver/Dockerfile)
-rstudio          |  Adds rstudio                             | [![](https://images.microbadger.com/badges/image/cboettig/rstudio.svg)](https://microbadger.com/) [![](https://img.shields.io/badge/Dockerfile-v3.3.2-blue.svg)](https://github.com/rocker-org/rocker/blob/master/rstudio/3.3.2/Dockerfile)  [![](https://img.shields.io/badge/Dockerfile-latest-blue.svg)](https://github.com/rocker-org/rocker-versioned/blob/master/rstudio/Dockerfile)  
+rstudio          |  Adds rstudio                             | [![](https://images.microbadger.com/badges/image/rocker/rstudio-stable.svg)](https://microbadger.com/) [![](https://img.shields.io/badge/Dockerfile-v3.3.2-blue.svg)](https://github.com/rocker-org/rocker/blob/master/rstudio/3.3.2/Dockerfile)  [![](https://img.shields.io/badge/Dockerfile-latest-blue.svg)](https://github.com/rocker-org/rocker-versioned/blob/master/rstudio/Dockerfile)  
 tidyverse        |  Adds tidyverse & devtools                | [![](https://images.microbadger.com/badges/image/rocker/tidyverse.svg)](https://microbadger.com/images/rocker/tidyverse) [![](https://img.shields.io/badge/Dockerfile-v3.3.2-blue.svg)](https://github.com/rocker-org/rocker-versioned/blob/master/tidyverse/3.3.2/Dockerfile) [![](https://img.shields.io/badge/Dockerfile-latest-blue.svg)](https://github.com/rocker-org/rocker-versioned/blob/master/tidyverse/Dockerfile)  
 verse            |  Adds tex & publishing-related packages   | [![](https://images.microbadger.com/badges/image/rocker/verse.svg)](https://microbadger.com/images/rocker/verse) [![](https://img.shields.io/badge/Dockerfile-v3.3.2-blue.svg)](https://github.com/rocker-org/rocker-versioned/blob/master/verse/3.3.2/Dockerfile)  [![](https://img.shields.io/badge/Dockerfile-latest-blue.svg)](https://github.com/rocker-org/rocker-versioned/blob/master/verse/Dockerfile)