Account for permissions in pub link on post draft page #2

When viewing a post draft, the pub title at the top is clickable. Currently it always links to the logged in pub dashboard url.

But if you're not the pub creator, it should instead link to the public homepage of the publication. This should be the case whether viewing the edit or view-only link, the important thing is whether you have access to the pub dashboard (i.e. if you're the pub creator).