sudo tee /etc/polkit-1/rules.d/99-mintupdate.rules > /dev/null << 'EOF'
polkit.addRule(function(action, subject) {
if (action.id == "org.aptkit.install-or-remove-packages" &&
subject.user == "username") {
return polkit.Result.YES;
}
});
EOF
then either reboot or restart the polkit service:
sudo systemctl restart polkit