generator/host: Handle unspecified APT checking mode properly

generate-icinga-generic-host.py

@@ -267,9 +267,9 @@ def create_icinga2_host_object_from_netbox(netbox, device_name):
         elif apt == "passive":
             host.add_apt_passive()
         else:
-            raise Exception(
-                    f"Invalid apt configuration '{apt}'! "
-                    "Must be either active or passive")
+            # Not one of the predefined values means APT checking is not
+            # enabled
+            pass
     except KeyError:
         pass