test: Add environment variable to disable check for unexpected SELinux messages
test: Add environment variable to disable check for unexpected SELinux messages

Unexpected SELinux messages often get in the way for testing external
modules and also older downstream versions on newer images, so provide a
knob to skip this part.

Closes #8642

SotolitoLabs/cockpit,cockpituous/cockpit,deryni/cockpit,martinpitt/cockpit,mareklibra/cockpit,deryni/cockpit,garrett/cockpit,deryni/cockpit,mareklibra/cockpit,stefwalter/cockpit,stefwalter/cockpit,stefwalter/cockpit,moraleslazaro/cockpit,mareklibra/cockpit,deryni/cockpit,deryni/cockpit,martinpitt/cockpit,mvollmer/cockpit,cockpit-project/cockpit,SotolitoLabs/cockpit,deryni/cockpit,stefwalter/cockpit,andreasn/cockpit,SotolitoLabs/cockpit,mareklibra/cockpit,cockpituous/cockpit,moraleslazaro/cockpit,garrett/cockpit,mvollmer/cockpit,andreasn/cockpit,cockpituous/cockpit,moraleslazaro/cockpit,deryni/cockpit,andreasn/cockpit,moraleslazaro/cockpit,martinpitt/cockpit,cockpit-project/cockpit,SotolitoLabs/cockpit,SotolitoLabs/cockpit,SotolitoLabs/cockpit,mareklibra/cockpit,andreasn/cockpit,cockpituous/cockpit,cockpit-project/cockpit,moraleslazaro/cockpit,martinpitt/cockpit,garrett/cockpit,garrett/cockpit,stefwalter/cockpit,mareklibra/cockpit,mvollmer/cockpit,andreasn/cockpit,moraleslazaro/cockpit,mvollmer/cockpit,stefwalter/cockpit,martinpitt/cockpit,cockpit-project/cockpit,mvollmer/cockpit,cockpituous/cockpit,stefwalter/cockpit,andreasn/cockpit,garrett/cockpit,SotolitoLabs/cockpit,cockpituous/cockpit,mareklibra/cockpit,andreasn/cockpit,moraleslazaro/cockpit,cockpit-project/cockpit