Super sidebar toggle button when HAML breadcrumbs hidden

From: !114676 (comment 1347604735)

There is no sidebar toggle button (when collapsed) for the new project/group pages because they set @hide_breadcrumbs to true and recreate in Vue with GlBreadcrumb. We may want to create a top-bar Vue component which contains the toggle button and GlBreadcrumb for these views to use.