Fixes #15126: group field should be optional when creating VPN tunnel via REST API

netbox/vpn/api/serializers.py

@@ -46,7 +46,10 @@ class TunnelSerializer(NetBoxModelSerializer):
     status = ChoiceField(
         choices=TunnelStatusChoices
     )
-    group = NestedTunnelGroupSerializer()
+    group = NestedTunnelGroupSerializer(
+        required=False,
+        allow_null=True
+    )
     encapsulation = ChoiceField(
         choices=TunnelEncapsulationChoices
     )

netbox/vpn/tests/test_api.py

@@ -105,7 +105,6 @@ class TunnelTest(APIViewTestCases.APIViewTestCase):
             {
                 'name': 'Tunnel 6',
                 'status': TunnelStatusChoices.STATUS_DISABLED,
-                'group': tunnel_groups[1].pk,
                 'encapsulation': TunnelEncapsulationChoices.ENCAP_GRE,
             },
         ]