Update layout for Readme view of Project Overview

Proposal

With Project overview page updates (#429186 - closed) we are updating the page layout for the project overview.

For the README content view of the project overview, we are adding a link to "Files" so that users can navigate to the code.

From #24746 (comment 1562768879)

I've just switched mine to "Readme" and now it's a nightmare to easily find the actual files.

Current	Proposal