docs(punctuation): clarify guidelines for ellipsis

The punctuation documentation for ellipsis conflicts with the button label documentation with regards to when to use an ellipsis in conjunction with an action that requires additional input from the user.

Elipse punctuation

Omit from menu items or buttons that open a modal or start some other process.

Button Labels

Append an ellipsis (…) to the button label text when the action will require additional input from the user before final completion

Based on the discussions in #776 (closed) we should update the elipse punctuation documentation to align with button labels documentation