tests: enable 'use-default-netvm' while restoring old backup
tests: enable 'use-default-netvm' while restoring old backup

Firewall VM was named 'firewallvm' at that time.

QubesOS/qubes-core-admin,QubesOS/qubes-core-admin,QubesOS/qubes-core-admin,woju/qubes-core-admin,woju/qubes-core-admin,woju/qubes-core-admin,woju/qubes-core-admin,marmarek/qubes-core-admin,marmarek/qubes-core-admin,marmarek/qubes-core-admin