Use full printer name if no tag is known

Contributes to CL-1173

plugins/UM3NetworkPrinting/resources/qml/MonitorPrinterPill.qml

@@ -22,7 +22,7 @@ Item
             case "Ultimaker S5":
                 return "UM S5"
             default:
-                return ""
+                return text
         }
     }