[IMP] iot troubleshooting: add a troubleshooting item for printer

[viso-odoo]

In response to a recent ticket (opw-3940166), we are adding an item to the troubleshooting page of IoT configuration.

The item addresses when CUPS detects the same printer multiple times.

[robodoo]

[auva-odoo]

@robodoo up to 18.4

[robodoo]

@auva-odoo there is no branch '18.4', it can't be used as a forward port target.

[auva-odoo]

@robodoo up to saas-18.4

[robodoo]

Forward-porting to 'saas-18.4'.