Support for connectivity monitor to set ICMP payload size

[dgonzalez85]

Enhancement summary

Trying to replicate configurations for an AI deployment. In 4.27.2F we introduced the ability to configure in connectivity monitor the ICMP payload size such as:

monitor connectivity
   no shutdown
   !
   host {{ name }}
      ip {{ ip_to_monitor }}
      icmp echo size 9300

However we do not support this option yet in AVD:
https://avd.arista.com/5.1/roles/eos_cli_config_gen/docs/input-variables.html#monitor-connectivity

This TOI covers the configurations available to specify ICMP payload size:
https://www.arista.com/en/support/toi/eos-4-20-1f/13913-connectivity-monitor

Which component of AVD is impacted

eos_cli_config_gen

Use case example

Set the ICMP payload size for ICMP probes.

Describe the solution you would like

Support for icmp echo size via eos_cli_config_gen.

Describe alternatives you have considered

No response

Additional context

No response

Contributing Guide

• I agree to follow this project's Code of Conduct