Add a reference to csp_log in documentation

Because we wanted a decent CSP reporting log overview, we created the csp_log module (see https://www.drupal.org/project/csp_log → ). It can be used in the CSP module, but we made sure it could be used e.g. by seckit too. Do you think it's useful to add a reference to the documentation?

The module contains a list of CSP reports, but also aggregate reports to be able to take quick action.

If this is not useful, sorry for the overhead :)