feature: Sequential multiple artifact upload to model registry model versions

Merge request: !165274 (merged)

feature: Sequential multiple artifact upload to model registry model versions

Context

Upload artifacts to an existing machine learnin... (#456446 - closed) introduced an artifact uploader for existing model versions.

Assumed problem

• Users should be able to select multiple files and upload sequentially
• Gitlabdotcom performance should be considered, this feature envisions a sequential upload

Proposal

• Allow multiple selection
• Upload each file sequentially
• [-] A 1 second pause between uploads?

In #387580 (closed) we add an optional description field when importing a model.