Filters in research output display authority instead label

[Kallox]

Describe the bug
Filtering publications by an item, such as a person or an orgunit, displays the authority instead of the item label.

To Reproduce
Steps to reproduce the behavior:

1. Create a publication with an author related to a person item.
2. Go to the research outputs page.
3. Omit the advanced filter and click the search button.
4. Open the authors filter and select the author.
5. Look at the selected filter—you will notice that it displays the authority instead of the label.

Expected behavior
Selecting an author should display the label instead of the authority.

Related work
Link to any related tickets or PRs here.