Filter issues list by an epic in a subgroup

Proposal

I met with a Premium customer that was expecting to be able to filter the issues list based on a specific epic created at a lower subgroup, but they were unable to. It seems the scoped filter only applies to epics created/managed from the same level group.

Snippet from the Chorus recording if you are interested in hearing their use case directly (private link - accessible to GitLab team members with Chorus access): https://hello.chorus.ai/listen?guid=996cee59561e4f80adf10809efd6f0c9

@mushakov suggested a new issue to track this feature request so that child epics from other subgroups can be listed in the epic detail page.