Code sample for "active" Button include "outline" classes

[jodyheavener]

Small thing. I was looking through the Button component variations and noticed that the "active" style's code samples include classes present in the "outline" style. For example:

<button class="button button--outline button--active button--primary">
  Primary
</button>

Removing the button--outline class appears to retain the active style, any reason it should be left in there?