Add IPv6 Neighbor Discovery support to ip_neighbor module

[stalabi1]

SUMMARY

I added support for IPv6 Neighbor Discovery to the ip_neighbor module.

ISSUE TYPE

• Feature Pull Request

COMPONENT NAME

sonic_ip_neighbor

OUTPUT

regression-2024-09-13-15-17-02.html.pdf
diff_output.log
delete_check_mode.log
merge_check_mode.log
facts_gathering.log

Checklist:

• I have performed a self-review of my own code to ensure there are no formatting, linting, or security issues
• I have verified that new and existing unit tests pass locally with my changes
• I have not allowed coverage numbers to degenerate
• I have maintained at least 90% code coverage
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• I have added tests that prove my fix is effective or that my feature works
• I have maintained backward compatibility or have provided any relevant "breaking_changes" descriptions in a "fragment" file in the "changelogs/fragments" directory of this repository.
• I have provided a summary for this PR in valid "fragment" file format in the "changelogs/fragments" directory of this repository branch. Reference : Ansible Change Log Document