Feat(eos_cli_config_gen): New improved ip_name_servers and deprecate name_server

[gmuloc]

Change Summary

Deprecate name_server in favor of ip_ name_servers in eos_cli_config_gen

NOTE TO REVIEWERS: for the change in the evpn_underlay_ebgp_overlay_ebgp molecule scenairo, I would be in favor of removing the test as it is already exercised in eos_designs_unit_tests scenario and there is no point in testing it twice.

Related Issue(s)

Fixes #2723

Component(s) name

arista.avd.eos_cli_config_gen

Proposed changes

• add the new schema fragment with newer model:

  ip_name_servers:
    - ip_address: <str>
      vrf: <str>
      priority: <int>

• add deprecation to old schema fragment
• fix eos and documentation templates
• fix all documentation using the legacy model (hello custom_structured_configuration examples)
• add porting guide
• move molecule test for deprecated model to eos_cli_config_gen_deprecatd_vars scenario
• create molecule test for new model in eos_cli_config_gen
• fix eos_designs base python module to render the new model
• re-run all molecule

How to test

molecule tests

Checklist

Repository 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 and documentation have been updated accordingly.
• I have updated molecule CI testing accordingly. (check the box if not applicable)

[ClausHolbechArista]

I don't think this is a breaking change right?

[gmuloc]

I don't think this is a breaking change right?

Indeed - this will just trigger a deprecation warning - let me change the PR name

[emilarista]

LGTM!