[Issue] VM IPv6 configuration blank/empty because subnet missing in IPV6 configuration

-
[Create an Internet-facing load-balancer with a Public IPv6 address](https://github.com/Azure/azure-quickstart-templates/tree/master/201-load-balancer-ipv6-create)

### Issue Details

VM IPv6 configuration blank/empty

Subnet missing

Code : https://github.com/Azure/azure-quickstart-templates/blob/master/201-load-balancer-ipv6-create/azuredeploy.json#L148

Fix: Add following for subnet in IPv6 configuration for interface (VM)

```json
"subnet": {
"id": "[resourceId('Microsoft.Network/virtualNetworks/subnets',variables('vnetName'), variables('subnetName'))]"
},
```

Open 201-load-balancer-ipv6-create/azuredeploy.json and inspect the VM IPv6 configuration around line 148. Compare it with the referenced load-balancer template context and verify that the subnet is present in the interface configuration. Done means the IPv6 VM configuration no longer appears blank and includes the intended subnet.

Written by the indexing model from the issue text.