Port away from deprecated KBookmarksmenu API
Summary:
Needs to wait until we can depend on 5.65
See D25660 for context
Reviewers: Dolphin, elvisangelaccio
Reviewed By: Dolphin, elvisangelaccio
Subscribers: kfm-devel
Tags: Dolphin
Differential Revision: https://phabricator.kde.org/D25665