Validation action fixes

[qstokkink]

Related to #58, the action fixes will have to be verified in another PR.

This PR:

• Updates the GitHub validation Action to only run on Python 3.9 and Python 3.10.
• Updates content_discovery.test_community to be IPv6 compatible.
• Updates rendezvous.test_community to be IPv6 compatible.

[qstokkink]

validate