Update test data and fix e2e tests

brian_polling_manager/interface_stats/juniper.py

brian_polling_manager/interface_stats/nokia.py

test/interface_stats/conftest.py

test/interface_stats/data/capture-test-data-nokia.py

test/interface_stats/data/capture-test-data.py

test/interface_stats/data/error-interfaces.json

test/interface_stats/data/gws-indirect.json

...erface_stats/data/mx1.ams.nl.geant.net-interface-info.xml

...rface_stats/data/mx1.ath2.gr.geant.net-interface-info.xml

...erface_stats/data/mx1.buc.ro.geant.net-interface-info.xml

test/interface_stats/data/mx1.buc.ro.geant.net-juniper.xml

...erface_stats/data/mx1.bud.hu.geant.net-interface-info.xml

test/interface_stats/data/mx1.bud.hu.geant.net-juniper.xml

...erface_stats/data/mx1.dub.ie.geant.net-interface-info.xml

test/interface_stats/data/mx1.dub.ie.geant.net-juniper.xml

...erface_stats/data/mx1.gen.ch.geant.net-interface-info.xml

test/interface_stats/data/mx1.gen.ch.geant.net-juniper.xml

...erface_stats/data/mx1.lon.uk.geant.net-interface-info.xml

test/interface_stats/data/mx1.lon.uk.geant.net-juniper.xml

...rface_stats/data/mx1.lon2.uk.geant.net-interface-info.xml