vyos_interfaces integration tests fail on 1.2 and above.

There appear to be a number of causes:

• unnecessary quoting on disabled in _parsed_config.cfg is causing the parsed tests to fail
• interfaces that exist (eth3 in particular) and are not expected can be a problem ( need to determine if eth3 is necessary or now, if not we can just put that in the cookbook of how to run the tests)
• discrepencies in populate variable vs the handling of defaults in the current code (in particular whether duplex and speed are reported if they are set to auto