Provide feedback as soon as the image is changed

Subject: Repository > Settings > Repository details > Change avatar

After the repository avatar has been uploaded and the "save" action has been executed, the new avatar will be saved. However, in the current view (Repository details) the user does not get any feedback that the repository avatar has been changed. The current repository avatar is not displayed. After loading the view (Repository details) again, the current repository avatar is displayed.

The following could be improved

1. a text feedback: "Repository avatar successfully updated"
2. The new avatar is displayed immediately.