[feat] Add size enum prop to Address

[ahobson]

Does your feature request relate to a specific USWDS feature?
Footer component - specifically the <Address/> subcomponent.

Is your feature request related to a problem? Please describe.
Discussion of problem is in #187.

Describe the solution you'd like

• Add new size prop.
• Deprecate big, medium, slim props in favor of new prop.
• Add new tests and adjust stories as needed.

This work should look very similar to #229.

Describe alternatives you've considered
n/a, we converged on a solution for handling these cases in the linked issue.