[bug][network] swagger definition doesn't follow server behavior

For REST API https://github.com/Azure/azure-rest-api-specs/blob/b34740ddec859f5a55ba176a3ccba39335b16ad4/specification/network/resource-manager/Microsoft.Network/stable/2024-05-01/loadBalancer.json#L1464-L1536

Its real service response is:

{
  "up": 1,
  "down": 1,
  "loadBalancerBackendAddresses": [
    {
      "ipAddress": "<REDACTED>",
      "networkInterfaceIPConfigurationId": "/subscriptions/<REDACTED>/resourceGroups/<REDACTED>/providers/Microsoft.Network/networkInterfaces/<REDACTED>/ipConfigurations/sslvpn",
      "state": "Up",
      "reason": "Up_Probe_Success"
    },
    {
      "ipAddress": "<REDACTED>",
      "networkInterfaceIPConfigurationId": "/subscriptions/<REDACTED>/resourceGroups/<REDACTED>/providers/Microsoft.Network/networkInterfaces/<REDACTED>/ipConfigurations/failover",
      "state": "Down",
      "reason": "Down_Probe_TcpProbeTimeout"
    }
  ]
}

We can see that for networkInterfaceIPConfigurationId, its swagger definition is object however the real response is string which doesn't correspond.

Expected behavior

Swagger definition shall follow real service behavior.

Open specification/network/resource-manager/Microsoft.Network/stable/2024-05-01/loadBalancer.json and compare the response definition at lines 1464-1536 with the networkInterfaceIPConfigurationId definition at lines 2842-2844. Verify the service response shape shown in the issue, then update the specification so the schema matches it and confirm the API specification remains valid.