Feat(eos_designs): Add support for `ethernet switchport default` in eos_designs

[gmuloc]

Enhancement summary

• follow up from Feat(eos_designs): Umbrella issue: Better support for existing eos_cli_config_gen keys in eos_designs #6265
• need to take into account the TODO from Refactor(eos_designs): Centralize parent interface generation for subinterfaces #6594
• would also need to be honored when rendering / not rendering switchport / no switchport everywhere in eos_designs (very simple ;) )

Which component of AVD is impacted

eos_designs

Use case example

cf summary

Describe the solution you would like

cf summary

Describe alternatives you have considered

No response

Additional context

No response

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