amp-story-page-attachment covers two different UX patterns (inline and outlink) and isn't semantic.
A new component name for outlinks will help communicate function.

The new name will be: amp-story-page-outlink

amp-story-page-outlink will point to the code in amp-story-page-attachment for backwards compatibility.

To do this:

1. Register element in amp-story.js
2. Create validation rules (can copy paste most validation from amp-story-page-attachment)

@ampproject/wg-stories