Recommendations on homepage

[niraymak]

Description

This PR shows project recommendations on the new home page.

Type of change

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• This change requires a documentation update

Checklist

• My code follows the style guidelines of this project
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• I have added tests that prove my fix is effective or that my feature works
• I updated the changelog with an end-user readable description
• I assigned this pull request to the correct project board to update the sprint board

Steps to Test or Reproduce

If you can't run the backend in Docker I recommend to hardcode an array of projects in the recommendation service.

1. Hardcode return statement of recommendationservice.
2. Run backend (identity, API)
3. Run frontend, log in with any user.
4. Hardcoded recommendation should show up above "What is DeX".

To test this feature you should run all backend containers except the notificationsystem and jobscheduler.

1. Run backend
2. Log in with "bob", "bob"
3. Call /api/project/export endpoint to synchronize MSSQL with ElasticSearch
4. Make sure 2 different users have 1 similar like (like on same project) and 3 different likes (like on a project the other user doesn't like).
5. Go to home page logged in as one of the two users.
6. See project recommendations above "What is DeX".

If unclear, please contact me.

Link to issue

Closes: #497

[waltersajtos]

Please wait with fixing this merge conflict until the homepage is merged