fix(backend): Restore sort

backend/tests/services/learning-path/learning-path-service.test.ts

@@ -48,7 +48,7 @@ describe('LearningPathService', () => {
             expect(result.data?.length).toBe(1);
 
             // Should include all the nodes, even those pointing to foreign learning objects.
-            expect([...result.data![0].nodes.map((it) => it.learningobject_hruid)].sort((a, b) => a - b)).toEqual(
+            expect([...result.data![0].nodes.map((it) => it.learningobject_hruid)].sort()).toEqual(
                 example.learningPath.nodes.map((it) => it.learningObjectHruid).sort()
             );
         });