Describe the bug:
A link tag configured via URL field formatter should not be rendered if the field has no data. Otherwise, the link would be broken.

Steps to reproduce:

1. Configure a URL field formatter for a field which has missing values in some documents
2. Check the result in the Discover table

Check other field formatters if they are affected by the same bug. For example, defining a Badge formatter also triggers an exception in the flyout for boolean field types.

Expected behavior:
No links should be rendered for cells where field did not have any value. It used to render - in earlier versions instead.