Add support for subinterfaces as tenant l3_interfaces

[ClausHolbechArista]

Change Summary

Add support for subinterfaces as tenant l3_interfaces

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)
• Code style update (formatting, renaming)
• Refactoring (no functional changes)
• Documentation content changes
• Other (please describe):

Related Issue(s)

Fixes #857

Component(s) name

arista.avd.eos_designs

Proposed changes

        # List of L3 interfaces | Optional.
        # This will create IP routed interface inside VRF. Length of interfaces, nodes and ip_addresses must match.
        l3_interfaces:
          - interfaces: [ <interface_name1>, <interface_name2>, <interface_name3> ]
            ip_addresses: [ <IPv4_address/Mask>, <IPv4_address/Mask>, <IPv4_address/Mask> ]
            nodes: [ < node_1 >, < node_2 >, < node_1 > ]
            description: < description >
            enabled: < true | false >
            mtu: <mtu >

          # For sub-interfaces the dot1q vlan is derived from the interface name by default, but can also be specified.
          - interfaces: [ <interface_name1.sub-if-id>, <interface_name2.sub-if-id> ]
            encapsulation_dot1q_vlan: [ <vlan id>, <vlan id> ]
            ip_addresses: [ <IPv4_address/Mask>, <IPv4_address/Mask> ]
            nodes: [ < node_1 >, < node_2 > ]
            description: < description >
            enabled: < true | false >
            mtu: <mtu >

How to test

Added test of subinterfaces to molecule both with auto-derived vlan as well as manually specified vlan.

Checklist:

• My code has been rebased from devel before I start
• I have read the CONTRIBUTING document.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have updated molecule CI testing accordingly
• All new and existing tests passed (pre-commit, make linting and make sanity-lint).

[carlbuchmann]

LGTM!