Fetch KG project data and consider switching to that for getting descriptions and avatars

[lorenzo-cavazzi]

Description

KG has already implemented a solution for getting the project data and metadata from a "project" endpoint.
We should invoke that when we load a project and store the data into a new slice (API reference).
ℹ️ This is the only mandatory step for this issue, and we want to add that because KG will soon start keeping track of the last accesses to projects to delete obsolete metadata.

After this step, we should explore the possibility to use those data. The 2 most interesting parts are:

• Description: this is already added at creation time through renku-core. We should:
  • use the POST /renku/project.edit endpoint to edit the project description also from the project settings page (API reference)
  • verify how quickly that information is updated on KG (do we get the new description if we invoke the KG project API immediately after modifying it? how long does it take re-indexing in this specific case?)
  • If that's slow, verify using the renku-core API to fetch that property (API reference)
• Avatars: we should have support soon for that on renku core. The pattern would be similar to the one described above. Verify it's feasible and consider creating a follow-up issue.
• Other properties: do they come from the KG or are those taken directly from GitLab? In the second case, we can consume them right away and start phasing out GitLab for that... Verify with KG team this info, and create follow-up issue where necessary