Add user stories: Improving DPG discoverability on GH

[amreenp7]

Context It is challenging for users to find or navigate through relevant DPG projects and repos on Github. UNICEF is working with Github's Tech for Social Good team to identify experiments or coded prototypes to prove the value that specific feature additions or enhancements might bring (e.g. adding a "featured project" block to a user's dashboard page to recommend a DPG project to specific users).

• [x] Contribute to the concept document HERE
• [x] Determine next steps (e.g. follow-up meeting with Mala + team, creation of wireframes, etc).