Fix leftover old info in README

Author: AndiH

README.md

@@ -20,7 +20,7 @@ Walk-through:
 
 * Sign up at JuDoor: https://go.fzj.de/mg-jd
 * Open Jupyter JSC: https://jupyter-jsc.fz-juelich.de
-* Create new Jupyter instance on JUWELS, using training2446 account, on **LoginNodeBooster**
+* Create new Jupyter instance on JEDI, using training2446 account, on **LoginNode**
 * Source course environment: `source $PROJECT_training2446/env.sh`
 * Sync material: `jsc-material-sync`
 * Locally install NVIDIA Nsight Systems: https://developer.nvidia.com/nsight-systems