Document how to show debug logs on the logging page

[stooj]

Problem description

On the IaC -> Concepts -> Logging page, there are instructions on how to log at the debug level, and it says that those logs are hidden by default.

How do you make those logs show up? It's not documented on this page or on the troubleshooting page (-v controls engine logs).

To show the debug logs, you need to pass the --debug flag to pulumi, but I can't find where that is documented.

Suggestions for a fix

Add a note saying use the --debug | -d flag to show debug messages.