Feat(eos_designs): Add support for TerminAttr token-secure auth for on-premise CV

[ClausHolbechArista]

Change Summary

Add support for TerminAttr token-secure auth for on-premise CV

Related Issue(s)

Fixes #2025

Component(s) name

arista.avd.eos_designs

Proposed changes

• Sneaking a few fixes for porting guide in here

• Changing behavior if ingestkey is not set, to instead configure token auth.
  This is non breaking for any deployments, since they would have the key set already.
  CV will deprecate support for key based auth soon, so we need to move people towards
  cert based auth also for on-prem.

  On-premise CVP ingest auth key. If set, terminattr will be configured with key-based authentication for on-premise CVP.
  If not set, terminattr will be configured with certificate based authentication using token-secure onboarding.
  Token must be copied to the device first.

How to test

Added molecule test without key.
No changes to other molecule scenarios having keys set.

Checklist

User Checklist

• N/A

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)

[gmuloc]

Only comment about making terminattr -> TerminAttr for comments / descriptions to be consistent with some other buts of the doc (in the schema as well)

[carlbuchmann]

LGTM

[noredistribution]

one quick comment here, token-secure method is only supported on CVaaS, whereas on on-prem it has to be token
they are essentially the same mechanism but token-secure will only work on CVaaS and token will only work on on-prem, so we will have to make sure to use "method": "token" unless CVaaS is used in which case it's `"method": "token-secure"