Chapter 3 - Manage cron jobs

" If you want to run a shell script on all the servers every day at 4 a.m., add the cron job with: "

```
$ ansible multi -b -m cron -a "name='daily-cron-all-servers' \
hour=4 job='/path/to/daily-script.sh'”
```

But this runs the cron every minute of the hour because `minute` has default value `*`.

To run the cron only once at 4 a.m., we need to add `minute=0` to the command.

Review the Chapter 3 cron-job example shown in the issue and confirm the Ansible cron module's default minute behavior. Update the example so it runs once at 4 a.m. by specifying minute=0, then check the rendered chapter to ensure the command and explanation agree.

Written by the indexing model from the issue text.