test: Update router6 test to use new API
test: Update router6 test to use new API

hioa-cs/IncludeOS,AndreasAakesson/IncludeOS,alfred-bratterud/IncludeOS,alfred-bratterud/IncludeOS,AnnikaH/IncludeOS,AnnikaH/IncludeOS,mnordsletten/IncludeOS,alfred-bratterud/IncludeOS,AndreasAakesson/IncludeOS,mnordsletten/IncludeOS,alfred-bratterud/IncludeOS,hioa-cs/IncludeOS,AndreasAakesson/IncludeOS,mnordsletten/IncludeOS,AndreasAakesson/IncludeOS,mnordsletten/IncludeOS,hioa-cs/IncludeOS,AnnikaH/IncludeOS,alfred-bratterud/IncludeOS,AndreasAakesson/IncludeOS,AnnikaH/IncludeOS,AndreasAakesson/IncludeOS,hioa-cs/IncludeOS,mnordsletten/IncludeOS,hioa-cs/IncludeOS,AnnikaH/IncludeOS,mnordsletten/IncludeOS