Issue description

Having more than 7 Traits defined shows that chooser box in Traits Tab in Personas app is badly styled.

Steps to reproduce

1. Add more Traits (at least 4) in here: link (copy-paste existing 4 items)
2. Open Segments App and switch to Traits Tab
3. Click on Add (Note how dialog looks)
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4. Open Personas App and switch to Traits Tab
5. Click on Add (The selection box ends in half of the dialog and the action bar isn't used in this case) (See Personas.png)

Note

I would expect Personas app would have the same styling of Traits chooser as it is in Segments app (which also without the actionbar which doesn't make sense in the case of radio-button chooser)