Badge: add styles for additional spec'd features

[hunterloftis]

Description

There are a couple features in the badge spec that aren't implemented yet in CSS:

• icons
• fixed placement styling

Why do you need this feature or component?

Right now I'm adding these features to the SWC implementation on top of the existing CSS in adobe/spectrum-web-components#2305

[pfulton]

Completed as part of our migration to @adobe/spectrum-tokens