Show issues of subgroups in group-level issue board

• In the current implementation of group issue boards (https://gitlab.com/gitlab-org/gitlab-ee/issues/928), we only show issues across all projects of that group.
• It would be vastly helpful to show issues of projects that belong to subgroups of that particular group.
• How should the UI behave?

Consider:

• group-a/group-aa/group-aaa/project-1
• group-a/group-aa/group-aab/project-2
• group-a/group-aa/group-aac/project-3
• group-a/group-ab/group-aba/project-4
• group-a/group-ac/project-5
• group-a/project-6

A group board for group-a should contain all issues in all project-1, project-2, project-3, project-4, project-5, project-6.

A group board for group-aa should contain all issues in all project-1, project-2, project-3.

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changed milestone to %Next 2-3 months

marked this issue as related to #928 (closed)

mentioned in issue #928 (closed)

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@victorwu Some side note: As currently sub-groups doesn't inherit the parent's group labels you might run into issues here in case a "board lane" is bound to a particular label ID. E.g. you might end up with two In Progress lanes when both the parent group and the sub-group defines a In Progress label.

changed the description