Merge branch 'work-items-widgets-migration' into 'master'

Work items child widget: Migrate to crud

See merge request https://gitlab.com/gitlab-org/gitlab/-/merge_requests/161888



Merged-by: Florie Guibert <fguibert@gitlab.com>
Approved-by: Annabel Dunstone Gray <annabel.dunstone@gmail.com>
Approved-by: Florie Guibert <fguibert@gitlab.com>
Reviewed-by: Florie Guibert <fguibert@gitlab.com>
Reviewed-by: Sascha Eggenberger <seggenberger@gitlab.com>
Co-authored-by: Sascha Eggenberger <seggenberger@gitlab.com>