Fixed the failing content view tests in jenkins

Please review it
thanks

The tests fixed : 

tests.foreman.cli.test_contentviews.TestContentView.test_associate_view_rh
tests.foreman.cli.test_contentviews.TestContentView.test_associate_view_rh_custom_spin
tests.foreman.cli.test_contentviews.TestContentView.test_cv_promote_rh
tests.foreman.cli.test_contentviews.TestContentView.test_cv_publish_rh
Can this message be updated to include the actual `result.return_code`? The actual return code can be very useful when the assertion fails.