1.7.1 Ensure GNOME Display Manager is removed

Audit

Run the following command and verify gdm3 is not installed:

# dpkg-query -s gdm3 &>/dev/null && echo "gdm3 is installed"
gdm3 unknown ok not-installed not-installed

Nothing should be returned

Remediation

Run the following command to uninstall gdm3 and remove unused dependencies:

# apt purge gdm3
# apt autoremove gdm3