Groups: Add Recommended groups functionality

[AlexTr]

Continue enhancements from #4397

• [ ] 1. Geographic information - suggest groups with members nearby
• [ ] 2. Demographic information, like language and age, to suggest groups with similar members
• [ ] 5. Trending or popular topics in groups
• [ ] 6. Information you’ve added to your profile, like your interests (labels/channels) that are also associated with a group