test: Fix vm-run --network
test: Fix vm-run --network

Commit b772ad739 moved from the external network-cockpit.xml to an
inline definition, but forgot to configure NAT. This broke networking
with "vm-run --network <image>". Put it back.

deryni/cockpit,mareklibra/cockpit,larskarlitski/cockpit,larsu/cockpit,deryni/cockpit,mareklibra/cockpit,SotolitoLabs/cockpit,mvollmer/cockpit,deryni/cockpit,garrett/cockpit,Scribery/cockpit,andreasn/cockpit,moraleslazaro/cockpit,martinpitt/cockpit,deryni/cockpit,larskarlitski/cockpit,moraleslazaro/cockpit,harishanand95/cockpit,stefwalter/cockpit,Scribery/cockpit,harishanand95/cockpit,cockpit-project/cockpit,mareklibra/cockpit,cockpituous/cockpit,Scribery/cockpit,andreasn/cockpit,martinpitt/cockpit,SotolitoLabs/cockpit,garrett/cockpit,stefwalter/cockpit,larskarlitski/cockpit,moraleslazaro/cockpit,petervo/cockpit,harishanand95/cockpit,larsu/cockpit,cockpit-project/cockpit,cockpituous/cockpit,garrett/cockpit,mvollmer/cockpit,harishanand95/cockpit,andreasn/cockpit,stefwalter/cockpit,petervo/cockpit,larsu/cockpit,andreasn/cockpit,martinpitt/cockpit,petervo/cockpit,mareklibra/cockpit,petervo/cockpit,deryni/cockpit,harishanand95/cockpit,garrett/cockpit,moraleslazaro/cockpit,moraleslazaro/cockpit,larskarlitski/cockpit,SotolitoLabs/cockpit,martinpitt/cockpit,Scribery/cockpit,Scribery/cockpit,Scribery/cockpit,stefwalter/cockpit,cockpituous/cockpit,petervo/cockpit,mvollmer/cockpit,larskarlitski/cockpit,cockpituous/cockpit,mareklibra/cockpit,cockpit-project/cockpit,larsu/cockpit,harishanand95/cockpit,andreasn/cockpit,andreasn/cockpit,larskarlitski/cockpit,stefwalter/cockpit,mvollmer/cockpit,moraleslazaro/cockpit,SotolitoLabs/cockpit,harishanand95/cockpit,SotolitoLabs/cockpit,andreasn/cockpit,mareklibra/cockpit,cockpituous/cockpit,mareklibra/cockpit,moraleslazaro/cockpit,stefwalter/cockpit,Scribery/cockpit,larskarlitski/cockpit,petervo/cockpit,SotolitoLabs/cockpit,cockpit-project/cockpit,deryni/cockpit,larsu/cockpit,garrett/cockpit,petervo/cockpit,cockpituous/cockpit,martinpitt/cockpit,deryni/cockpit,stefwalter/cockpit,SotolitoLabs/cockpit,cockpit-project/cockpit,mvollmer/cockpit,larsu/cockpit