741bcd485d
Motivation: 86dd3886374323ac1ac8011b4a4716706bb7c47b reverted the usage of IPv6 Multicast test. This commit makes the whole multicast testing a lot more robust by selecting the correct interface in any case and also reverts the `@Ignore` Modifications: - More robust multicast testing by selecting the right NetworkInterface - Remove the `@Ignore` again for the IPv6 test Result: More robust multicast testing