Documentation fails to build with HUGO 0.111

@martin.lueders : While trying to build the documentation for release_14.0, I am getting some error in the HUGO log like

Error: Error building site: "..../content/Developers/Code_Documentation/_index.md:7:1": failed to extract shortcode: shortcode "children" must be closed or self-closed

This seems to be a bugfix in the version 0.111 that make this appear, see https://discourse.gohugo.io/t/what-is-meant-by-closed-or-self-closed/44785/13

I will try to fix this locally and prepare a merge request for this.