tests: machines: remove fixed names from the testCreate
tests: machines: remove fixed names from the testCreate

Previously we were setting manually the names for each Vm in the
testCreate test.
The names had a suffix with an increasing ID, which made adding/removing code
pieces in that test cumbersome. Replace the fixed name with an auto-created
name where possible.

deryni/cockpit,martinpitt/cockpit,mvollmer/cockpit,deryni/cockpit,moraleslazaro/cockpit,garrett/cockpit,mvollmer/cockpit,mvollmer/cockpit,deryni/cockpit,garrett/cockpit,cockpit-project/cockpit,deryni/cockpit,martinpitt/cockpit,garrett/cockpit,cockpituous/cockpit,moraleslazaro/cockpit,moraleslazaro/cockpit,deryni/cockpit,garrett/cockpit,moraleslazaro/cockpit,garrett/cockpit,deryni/cockpit,cockpit-project/cockpit,moraleslazaro/cockpit,mvollmer/cockpit,martinpitt/cockpit,martinpitt/cockpit,cockpituous/cockpit,cockpit-project/cockpit,cockpit-project/cockpit,cockpit-project/cockpit,deryni/cockpit,mvollmer/cockpit,martinpitt/cockpit,moraleslazaro/cockpit,cockpituous/cockpit,cockpituous/cockpit,moraleslazaro/cockpit,cockpituous/cockpit,cockpituous/cockpit