test_fault_tolerance: Fix race condition when checking artifact name.
test_fault_tolerance: Fix race condition when checking artifact name.

Make sure the deployment has finished and the name is written before
checking it.

Changelog: None

Signed-off-by: Kristian Amlie <505e66ae45028a0596c853559221f0b72c1cee21@northern.tech>

pasinskim/integration,pasinskim/integration,pasinskim/integration