Test suite relies on ifconfig, that's not included anymore in Tails 3.0
Originally created by @intrigeri on #12602 (Redmine)
Regression against 2.x + I think this may break some magic we do in
post_snapshot_restore_hook
, which can make all kinds of tests relying
on a working Tor fragile, hence target version = 3.0.
Feature Branch: test/12602-fix-network-check