Differing ENI but same netplan (network config version 2)

'ipv6_slaac': {
        'expected_eni': textwrap.dedent("""\
            auto lo
            iface lo inet loopback
            auto iface0
            iface iface0 inet6 auto
                dhcp 0
        """).rstrip(' '),
        'expected_netplan': textwrap.dedent("""
            network:
                version: 2
                ethernets:
                    iface0:
                        dhcp6: true
        """).rstrip(' '),

vs.

 'dhcpv6_stateless': {
        'expected_eni': textwrap.dedent("""\
        auto lo
        iface lo inet loopback
        auto iface0
        iface iface0 inet6 auto
            dhcp 1
    """).rstrip(' '),
        'expected_netplan': textwrap.dedent("""
        network:
            version: 2
            ethernets:
                iface0:
                    dhcp6: true
    """).rstrip(' '),