`file_store` of `Ci::PipelineArtifact` is not updated by the uploader

The following discussion from !37969 (merged) should be addressed:

@dosuken123 started a discussion:

You'd likely need after_save :update_file_store, if: :saved_change_to_file? in order to correctly update file_store per storage type.

Edited Aug 20, 2020 by Max Orefice