Draft: Use membership inheritance in authorized groups

What does this MR do?

Depends on !69535 (merged)

When getting authorized groups for a user, we fetch also all descendant groups (if user is direct or indirect member of a group, the user gets access also to all subgroups).

Also EpicsFinder is updated so it doesn't check read_epic permission individually for each group.

Related to: #217937 (closed)

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