Resolving design manager warnings from theme-overrides.css

[jasonnrosa]

Types of change

• [X] Bug fix (change which fixes an issue)
• [ ] Enhancement (change which improves upon an existing feature)
• [ ] New feature (change which adds new functionality)

Description

There were a few warnings in the theme-overrides.css file that we found via the design manager. There were three incorrect references to field paths and one field reference that was outdated/no longer needed.

Checklist

• [X] I have read the CONTRIBUTING document.
• [X] My code follows the style guide requirements.
• [X] I have thoroughly tested my change.

People to notify CC: @TheWebTech and @ajlaporte