Error serving metrics - 3rd party devices

Hi,

Sorry about logging this as a new issue, but it is relating to 3rd party devices on the latest main. I have also tested against the latest tag "sha-963d177".

I have included just the first device logged to try make it more legible.

```An error has occurred while serving metrics:

625 error(s) occurred:

* collected metric "unms_device_enabled" { label: label: label: label: label: label: gauge: } was collected before with the same name and label values
* collected metric "unms_device_maintenance" { label: label: label: label: label: label: gauge: } was collected before with the same name and label values
* collected metric "unms_device_cpu" { label: label: label: label: label: label: gauge: } was collected before with the same name and label values
* collected metric "unms_device_ram" { label: label: label: label: label: label: gauge: } was collected before with the same name and label values
* collected metric "unms_device_uptime" { label: label: label: label: label: label: gauge: } was collected before with the same name and label values
* collected metric "unms_device_last_seen" { label: label: label: label: label: label: counter: } was collected before with the same name and label values
* collected metric "unms_interface_enabled" { label: label: label: label: label: label: label: label: label: label: gauge: } was collected before with the same name and label values
* collected metric "unms_interface_plugged" { label: label: label: label: label: label: label: label: label: label: gauge: } was collected before with the same name and label values
* collected metric "unms_interface_up" { label: label: label: label: label: label: label: label: label: label: gauge: } was collected before with the same name and label values
* collected metric "unms_interface_enabled" { label: label: label: label: label: label: label: label: label: label: gauge: } was collected before with the same name and label values
* collected metric "unms_interface_plugged" { label: label: label: label: label: label: label: label: label: label: gauge: } was collected before with the same name and label values
* collected metric "unms_interface_up" { label: label: label: label: label: label: label: label: label: label: gauge: } was collected before with the same name and label values
* collected metric "unms_interface_enabled" { label: label: label: label: label: label: label: label: label: label: gauge: } was collected before with the same name and label values
* collected metric "unms_interface_plugged" { label: label: label: label: label: label: label: label: label: label: gauge: } was collected before with the same name and label values
* collected metric "unms_interface_up" { label: label: label: label: label: label: label: label: label: label: gauge: } was collected before with the same name and label values
* collected metric "unms_interface_enabled" { label: label: label: label: label: label: label: label: label: label: gauge: } was collected before with the same name and label values
* collected metric "unms_interface_plugged" { label: label: label: label: label: label: label: label: label: label: gauge: } was collected before with the same name and label values
* collected metric "unms_interface_up" { label: label: label: label: label: label: label: label: label: label: gauge: } was collected before with the same name and label values```