tools: Fix smoke test for RPM based systems
tools: Fix smoke test for RPM based systems

Only on Debian-like OSes we expect cockpit.socket to run after package
installation, not on RPM-based ones. So for the latter, explicitly start
cockpit.socket.

Also fix the curl invocation to not silently fail on connection errors.

Closes #9625
deryni/cockpit,mvollmer/cockpit,cockpituous/cockpit,mareklibra/cockpit,mareklibra/cockpit,moraleslazaro/cockpit,martinpitt/cockpit,moraleslazaro/cockpit,moraleslazaro/cockpit,mareklibra/cockpit,andreasn/cockpit,martinpitt/cockpit,andreasn/cockpit,cockpit-project/cockpit,mvollmer/cockpit,moraleslazaro/cockpit,garrett/cockpit,deryni/cockpit,deryni/cockpit,moraleslazaro/cockpit,andreasn/cockpit,garrett/cockpit,martinpitt/cockpit,martinpitt/cockpit,cockpituous/cockpit,garrett/cockpit,moraleslazaro/cockpit,cockpituous/cockpit,deryni/cockpit,cockpit-project/cockpit,deryni/cockpit,moraleslazaro/cockpit,deryni/cockpit,mvollmer/cockpit,cockpituous/cockpit,mareklibra/cockpit,cockpituous/cockpit,mareklibra/cockpit,cockpituous/cockpit,garrett/cockpit,andreasn/cockpit,garrett/cockpit,andreasn/cockpit,mareklibra/cockpit,deryni/cockpit,andreasn/cockpit,martinpitt/cockpit,cockpit-project/cockpit,andreasn/cockpit,cockpit-project/cockpit,mvollmer/cockpit,cockpit-project/cockpit,mareklibra/cockpit,mvollmer/cockpit