[qem] yast2_lan regression prevention
We had a regression in yast2_lan due to https://bugzilla.suse.com/show_bug.cgi?id=1185967
While we don't expect this particular issue to reappear, considering our business ties with SAP, it makes sense to expand testing to be more focused on SAP-like usage.
It seems like
/tests/yast2_cmd/yast_lan.pm is "pretty close" to the issue and could be extended to check secondary interfaces in bit more depth.