test: Robustify services tests
test: Robustify services tests

The main thing was that test.service could be started by either of those
timers and then subsequent test would fail, as it was waiting for
test.service to be inactive.

Also cleanup and do more checks on overview unit state checking.

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