mgr/dashboard: check config opt permissions

mgr/dashboard: check config opt permissions

Getting the user object fails for a non-admin user. Check
the permissions directory if the user is allowed to access the
config options instead.

Fixes: https://tracker.ceph.com/issues/47331
Signed-off-by: Tatjana Dehler <tdehler@suse.com>
(cherry picked from commit 0942b022d0515d53e2e8742851b6aeb60f3379f9)

 Conflicts:
	src/pybind/mgr/dashboard/frontend/src/app/shared/components/telemetry-notification/telemetry-notification.component.spec.ts
	src/pybind/mgr/dashboard/frontend/src/app/shared/components/telemetry-notification/telemetry-notification.component.ts
- Resolved import conflicts in both files; Resolved TestBed conflict (we have to stick with TestBed.get(); in octopus vs. master
  TestBed.inject(); which is related to Angular 9 being used in master and is not backported to octopus