[FR] Propagate repository metadata for git_areas_of_code index patterns

[fioddor]

Metadata fed in projects.json file doesn't propagate to indices such as git_areas_of_code. I guess it is because they are created by studies.

At least in index patterns like git_areas_of_code it should be feasible, since each entry has its own repository.

[fioddor]

Private reference for my future self.