feat(List): Deprecate list as a component

Purpose

A list is simply semantic HTML formatting and isn't a component. See related issue and discussion in gitlab-org/gitlab-ui#1198 (comment 930969297) for more details.

Note: Some list components will remain in the UI kit (Figma) to be able to recreate in design what can be produced in markup today. The List component page will be removed, and the components moved to the Foundations > Typography > Typ components page.

Closes #1336 (closed)