fix(css): Button text ellipsis

What does this MR do?

This MR is a tiny MVC for: #758 (closed)

In this MR we attempt to add the smallest amount of code possible to enable two things:

1. Even padding on buttons as screens scale
2. Allow button text to truncate

Screenshots

Questions

UX: Do we need a specific width for the buttons to truncate?

FE: Should we add a storybook example as you have in the dropdowns MR?

Does this MR meet the acceptance criteria?

Conformity

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