Implement `join/leave_multicast_group()` for IPv6

[lucasvr]

This patch rebases @jgallagher's PR #602 to the tip of the main branch, adding support for IPv6 multicast groups.

As in the original PR, it is possible to join groups by sending an initial MLDv2 Report packet. In addition to PR #602, this PR also implements leave_multicast_group().

It is not yet possible to resend the change report or respond to queries.

[codecov[bot]]

Codecov Report

Attention: Patch coverage is 94.32314% with 13 lines in your changes are missing coverage. Please review.

Project coverage is 79.97%. Comparing base (4c27918) to head (6c06cd9). Report is 10 commits behind head on main.

:exclamation: Current head 6c06cd9 differs from pull request most recent head 20aa66b. Consider uploading reports for the commit 20aa66b to get more accurate results

Files	Patch %	Lines
src/iface/interface/igmp.rs	86.20%	4 Missing :warning:
src/iface/packet.rs	86.66%	4 Missing :warning:
src/iface/interface/ipv6.rs	94.91%	3 Missing :warning:
src/wire/ipv6option.rs	96.49%	2 Missing :warning:

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #914      +/-   ##
==========================================
+ Coverage   79.96%   79.97%   +0.01%     
==========================================
  Files          82       81       -1     
  Lines       28378    27831     -547     
==========================================
- Hits        22693    22259     -434     
+ Misses       5685     5572     -113     

:umbrella: View full report in Codecov by Sentry.
:loudspeaker: Have feedback on the report? Share it here.

[lucasvr]

Folks, I would appreciate if someone could review this PR. For symmetry, in addition to @jgallagher's original pull request, this PR implements leave_multicast_group(). This pair of functions is enough to commission and control devices that use the Matter protocol.

[thvdveld]

I think we can merge this now. Thank you for your PR!