Update "command line" lecture

The only problem with this lecture that I can remember is the general problem with Windows users

We could either try to get our hands on a Windows machine before the lecture and try to come up with a recommendation on how to connect to Levante, or hope that no Windows users will show up

lectures/command-line/slides.qmd

 ---
 title: "The command line"
 subtitle: "Controlling local and remote machines"
-author: "Lukas Kluft and Florian Ziemen"
 ---
 
 # Shell