#55 Can be assign a role to members of my Workgroup

Remove Owner on Workgroup (use role MASTER instead)
"find_citizen_by_id" not return user anymore, use "find_citizen_by_id_with_user" instead

src/test/sql/fixtures/3-fixture_workgroup.sql

@@ -19,7 +19,6 @@ begin
     end if;
 
     created_workgroup := jsonb_set(created_workgroup::jsonb, '{created_by}'::text[], jsonb_build_object('id', _citizen_id::text), true)::json;
-    created_workgroup := jsonb_set(created_workgroup::jsonb, '{owner}'::text[], jsonb_build_object('id', _citizen_id::text), true)::json;
     assert created_workgroup#>>'{created_by, id}' = _citizen_id::text, format('citizenId in workgroup must be the same as citizen, %s != %s', created_workgroup#>>'{created_by, id}', _citizen_id::text);
 
     -- upsert workgroup