Update documentation for Slurm task options

Clarify the usage of --ntasks-per-node in Slurm scripts.

Author: s-sajid-ali

docs/hpc/08_ml_ai_hpc/03_pytorch_dpp.md

@@ -174,7 +174,7 @@ Here is one possibility:
 export MASTER_PORT=$(expr 10000 + $(echo -n $SLURM_JOBID | tail -c 4) + $SLURM_ARRAY_TASK_ID)
 ```
 
-### --ntasks-per-node versus --ntasks
+### `--ntasks-per-node` versus `--ntasks`
 
 Be sure to use `--ntasks-per-node` and not `--ntasks` in your Slurm script.