Adding decorators to worker does not add them to included routers

[DanielEidlin]

Describe the bug
When adding decorators to a worker, those decorators are not added to the routers the worker includes.

To Reproduce

1. Create a worker with before and/or after decorators.
2. Create a router.
3. Use the worker to include the router.
4. Run the worker.
5. Observe that the decorators are never called when the router's tasks are being executed.

Expected behavior
The decorators added to the worker should run before/after every task defined using the included router.

Screenshots
None.