Add a “Contributed projects” tab on the project dashboard

In ux-research#7 (closed), we found that among 12 users:

5 users failed to find their 'Contributed Projects'. Of the 7 users who did find their 'Contributed Projects', 6 took an indirect path.

Recommendation:

Most users instinctively went to 'Your Projects' before ruling it out. Could we let users filter by 'Contributed Projects' on this page?

On the project dashboard, add a “Contributed projects” tab next to “Your projects”.