ensure retention set when super admin (#8819)

## Summary
- the superadmin branch returns early, make sure default retention is
set before that returns (graphql schema now enforces non-null retention)
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## How did you test this change?
- clicktesting locally
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## Are there any deployment considerations?
- no
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backend/private-graph/graph/schema.resolvers.go

@@ -7922,6 +7922,8 @@ func (r *queryResolver) Workspace(ctx context.Context, id int) (*model.Workspace
 		return nil, nil
 	}
 
+	r.SetDefaultRetention(workspace)
+
 	if r.isWhitelistedAccount(ctx) {
 		projects := []model.Project{}
 		if err := r.DB.WithContext(ctx).Order("name ASC").Model(&workspace).Association("Projects").Find(&projects); err != nil {
@@ -7941,8 +7943,6 @@ func (r *queryResolver) Workspace(ctx context.Context, id int) (*model.Workspace
 		return *p, p.WorkspaceID == id
 	})
 
-	r.SetDefaultRetention(workspace)
-
 	return workspace, nil
 }