Git rstudio - create logical commits: mention a workaround for a bug

[cecileherr]

A suggestion for this part of the course: https://inbo.github.io/git-course/course_rstudio.html#28_create_logical_commits

Unfortunately there is still a problem with (some versions of?) RStudio that makes it impossible to split the modifications in a single file into individual commits as described in the tutorial. In the commit panel, the "stage line" and "stage selection" buttons only work if the "context" is "all lines". If you select any other option as "context" (e.g. "5 line", ...), nothing happens.

This bug is described here with a simple workaround (select "context"= "all lines"). Since this bug has been around for years, it might be useful to mention the problem and the solution in the tutorial.