PublishMenu hides commands when there is no main command

Description

Steps to reproduce

1. Add one Command with `isMain: false` to the Publish menu (you can also use an add-on that does this, like the A/B Testing add-on).
2. Go to a content item that does not have a main command (e.g. locked content).

Expected: Command should be visible in the Publish menu.
Actual: Command is not visible, and the whole bottom section where it should be displayed is hidden as well.