Merge branch 'improve-achievement-form' into 'master'

Improve avatar filename display on achievement form

See merge request https://gitlab.com/gitlab-org/gitlab/-/merge_requests/148274



Merged-by: Artur Fedorov <afedorov@gitlab.com>
Approved-by: Lorenz van Herwaarden <lvanherwaarden@gitlab.com>
Approved-by: Artur Fedorov <afedorov@gitlab.com>
Reviewed-by: Lorenz van Herwaarden <lvanherwaarden@gitlab.com>
Co-authored-by: Lorenz van Herwaarden <lvanherwaarden@gitlab.com>
Co-authored-by: Lee Tickett <ltickett@gitlab.com>