test: Check image-customize error propagation
test: Check image-customize error propagation

Test that error codes from --run-command are successfully forwarded.  We
rely on this to detect a failure case in another test.

Closes #9436
mareklibra/cockpit,andreasn/cockpit,cockpituous/cockpit,martinpitt/cockpit,mareklibra/cockpit,martinpitt/cockpit,mareklibra/cockpit,andreasn/cockpit,SotolitoLabs/cockpit,garrett/cockpit,deryni/cockpit,deryni/cockpit,cockpit-project/cockpit,garrett/cockpit,mvollmer/cockpit,martinpitt/cockpit,andreasn/cockpit,deryni/cockpit,mareklibra/cockpit,garrett/cockpit,andreasn/cockpit,cockpit-project/cockpit,mvollmer/cockpit,moraleslazaro/cockpit,SotolitoLabs/cockpit,SotolitoLabs/cockpit,martinpitt/cockpit,deryni/cockpit,cockpituous/cockpit,garrett/cockpit,mvollmer/cockpit,cockpituous/cockpit,moraleslazaro/cockpit,cockpituous/cockpit,cockpit-project/cockpit,deryni/cockpit,mareklibra/cockpit,cockpit-project/cockpit,SotolitoLabs/cockpit,SotolitoLabs/cockpit,mareklibra/cockpit,moraleslazaro/cockpit,cockpituous/cockpit,andreasn/cockpit,cockpituous/cockpit,deryni/cockpit,mvollmer/cockpit,moraleslazaro/cockpit,moraleslazaro/cockpit,garrett/cockpit,moraleslazaro/cockpit,martinpitt/cockpit,SotolitoLabs/cockpit,SotolitoLabs/cockpit,moraleslazaro/cockpit,andreasn/cockpit,andreasn/cockpit,deryni/cockpit,mvollmer/cockpit,mareklibra/cockpit,cockpit-project/cockpit