you can find out where the WO cli command lives by typing:
$ which wo
While I cannot confirm that all installs are the same, that resulted in this for me:
/usr/local/bin/wo
and then you'd want to test our your CLI command, ensuring that it works as expected:
/usr/local/bin/wo stack restart
if that worked, and assuming that you'd want to run this at 5am every week, you'd add this to your crontab:
0 5 * * 1 /usr/local/bin/wo stack restart
...BUT, let me forewarn you to doublecheck that this is actually what you're trying to do. While I can't truly speak for others, I'd say that the majority of individuals would probably not want or need to run this command on a scheduled cron.