Update installing-on-top.md

Author: ocaisa

docs/installing-on-top.md

@@ -356,6 +356,7 @@ Our output is full of errors like
 What went wrong?
 
 !!! warning "`There are not enough slots available in the system to satisfy...`"
+
     If you see a different error which starts with `There are not enough slots available in the system to satisfy...`
     this is because you are trying to run an MPI job while already in a Slurm job context (perhaps an interactive
     JupyterHub job). Our workload here is really small so we can safely tell OpenMPI that is ok to overload the CPUs: