add swap partition to ubuntu code example

Example 1: create swapfile ubuntu

sudo dd if=/dev/zero of=/swapfile bs=1024 count=1048576

Example 2: disable swap ubuntu 18.04

check swap: free -m
off swap: sudo swapoff -v /swapfile
comment swap entry from: /etc/fstab
remove swap file: sudo rm /swapfile
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Identify configured swap devices and files with cat /proc/swaps.
Turn off all swap devices and files with swapoff -a.
Remove any matching reference found in /etc/fstab.
Optional: Destroy any swap devices or files found in step 1 to prevent their reuse. Due to your concerns about leaking sensitive information, you may wish to consider performing some sort of secure wipe.