feat(label): add support for overflow - #3339

Preview: https://patternfly-pr-3339.surge.sh

A11y report: https://patternfly-pr-3339-coverage.surge.sh

@mcarrano @mceledonia would you consider this change visually breaking? Wondering if this should be opt-in, or just the new default for labels.

I don't consider it visually breaking. Why wouldn't you want this? What do you think @mceledonia ? Also, isn't the Label component still beta?

@mcarrano a potential implication is if there are labels currently that exceed the width, the content that is currently visible will not be without having to hover the label to see a tooltip, and that could be unwanted. I think it's fine, since it sounds like it was an oversight not to have it in the first place, so it's more of a bug fix. I just wanted to clarify since the way we make the update in react could depend on wither a prop enables it or not.

@christiemolloy @mcoker I'm kind of torn on this one. I guess there could be cases where you would not want the label to truncate. Let me get some other design opinions. @mceledonia @maryshak1996 @kybaker @gdoyle1 what do you think? In your usage of labels, are there cases where you might not want a long label name to truncate?