Edit MCC or MNC of a Network Slice using POST duplicates existing subscriber

[patriciareinoso]

Describe the bug

When editing the MCC or the MNC on a Network Slice, using a POST operation. There is a new subscriber that is created.

To Reproduce

1. Create resources:

Create a Subscriber:

curl -v ${WEBUI_IP}:5000/api/subscriber/imsi-208930100007487 \
--header 'Content-Type: text/plain' \
--data '{
    "UeId":"208930100007487",
    "plmnId":"20893",
    "opc":"981d464c7c52eb6e5036234984ad0bcf",
    "key":"5122250214c33e723a5dd523fc145fc0",
    "sequenceNumber":"16f3b3f70fc2"
}'

Create a Device Group:

curl -v ${WEBUI_IP}:5000/config/v1/device-group/cows \
--header 'Content-Type: application/json' \
--data '{
    "imsis": [
        "208930100007487"
    ],
    "site-info": "demo",
    "ip-domain-name": "pool1",
    "ip-domain-expanded": {
        "dnn": "internet",
        "ue-ip-pool": "172.250.1.0/16",
        "dns-primary": "8.8.8.8",
        "mtu": 1460,
        "ue-dnn-qos": {
            "dnn-mbr-uplink": 20000000,
            "dnn-mbr-downlink": 200000000,
            "traffic-class": {
                "name": "platinum",
                "arp": 6,
                "pdb": 300,
                "pelr": 6,
                "qci": 8
            }
        }
    }
}'

Create a Network Slice:

curl -v ${WEBUI_IP}:5000/config/v1/network-slice/test2 \
--header 'Content-Type: application/json' \
--data '{
  "slice-id": {
    "sst": "1",
    "sd": "010203"
  },
  "site-device-group": [
    "cows"
  ],
  "site-info": {
    "site-name": "demo",
    "plmn": {
      "mcc": "208",
      "mnc": "03"
    },
    "gNodeBs": [
      {
        "name": "testpcf-gnbsim-gnbsim",
        "tac": 1
      }
    ],
    "upf": {
      "upf-name": "upf-external.testpcf.svc.cluster.local",
      "upf-port": "8805"
    }
  }
}'

2. Get Subscribers -> Only one subscribers exist. plmnID == MCC + MNC

$ curl  ${WEBUI_IP}:5000/api/subscriber
[{"plmnID":"20893","ueId":"imsi-208930100007487"}]

3. Edit the subscriber using POST and modify the MCC and MNC (123 and 45)

curl -v ${WEBUI_IP}:5000/config/v1/network-slice/test2 \
--header 'Content-Type: application/json' \
--data '{
  "slice-id": {
    "sst": "1",
    "sd": "010203"
  },
  "site-device-group": [
    "cows"
  ],
  "site-info": {
    "site-name": "demo",
    "plmn": {
      "mcc": "123",
      "mnc": "45"
    },
    "gNodeBs": [
      {
        "name": "testpcf-gnbsim-gnbsim",
        "tac": 1
      }
    ],
    "upf": {
      "upf-name": "upf-external.testpcf.svc.cluster.local",
      "upf-port": "8805"
    }
  }
}'

4. Get Subscribers

$ curl  ${WEBUI_IP}:5000/api/subscriber
[{"plmnID":"12345","ueId":"imsi-208930100007487"},{"plmnID":"20893","ueId":"imsi-208930100007487"}]

-> There are 2 subscribers. One with the original plmnID == MCC + MNC and another with plmnID == newMCC + newMNC

Expected behavior

Only one subscriber exists and its plmnID is newMCC + newMNC after POST.