media-sharing: Handle mime types consistently
See these comments for details:
https://invent.kde.org/kde/kaidan/merge_requests/351#note_8086 https://invent.kde.org/kde/kaidan/merge_requests/351#note_8101
See these comments for details:
https://invent.kde.org/kde/kaidan/merge_requests/351#note_8086 https://invent.kde.org/kde/kaidan/merge_requests/351#note_8101