Tails does not start: document workarounds to reach debug information

A user was able to bypass the greeter by removing ‘noautologin’ from the boot options: the desktop loads directly. Then it’s possible to get more informations with ‘sudo tails-debugging’, which works without admin password

This should be added somewhere in the documentation, maybe here:
https://tails.boum.org/doc/first_steps/bug_reporting/tails_does_not_start/#entirely

The documentation must say that the resulting system will have undefined (and potentially dangerous) behaviour and should not be used for anything else than bug reporting

Related issues

• Related to #11095 (closed)
• Related to #7323 (closed)
• Related to #15130

Original created by @elouann on 11392 (Redmine)