the updated vlan configuration is not applied after 'netplan apply'

[Ryoga Saito]

- I write the following configuration for Server.

```
network:
    ethernets:
        enp5s0f0:
            addresses:
            - 10.0.0.253/24
            dhcp4: false
            dhcp6: false
            gateway4: 10.0.0.254
            nameservers:
                addresses:
                - 8.8.8.8
                - 8.8.4.4
                search: []
        enp5s0f1: {}
    vlans:
        envp1:
            id: 101
            link: enp5s0f1
        envp2:
            id: 102
            link: enp5s0f1
        envp3:
            id: 103
            link: enp5s0f1
        envp4:
            id: 104
            link: enp5s0f1
        envp5:
            id: 105
            link: enp5s0f1
        envp6:
            id: 106
            link: enp5s0f1
    version: 2
```

- execute 'ip addr add 192.168.0.201/24 dev envp3'

I confirmed that Client (192.168.0.101/24) and Server communicated each other.

- and rewrite 'id: 103' to 'id: 105' and execute 'netplan apply'

I expected that Client and Server couldn't communicate, but still could.

I inspect this problem, and I found that systemd-networkd didn't update the setting for netdev.

and I found this: https://unix.stackexchange.com/questions/262000/systemd-networkd-how-to-force-new-configuration-without-reboot

so, I tried to execute 'ip link set enp5s0f1' before 'netplan apply'. then envp3 interface wasn't created.