Removed the code that was setting and using `@corporate_information_page` in https://github.com/alphagov/whitehall/commit/0438b64c157599e28d190fa3819d41017ed2ec37 so that everything now references `@edition`. 

`admin_corporate_information_pages_path` removed in https://github.com/alphagov/whitehall/commit/3dbc6b741eb69c9b7c6641ab7b91468f7d698d8d.