Modify example debug_task to ignore result

To allow:
```
debug_task.delay().get()
```

examples/django/proj/celery.py

@@ -17,6 +17,6 @@
 app.autodiscover_tasks()
 
 
-@app.task(bind=True)
+@app.task(bind=True, ignore_result=True)
 def debug_task(self):
     print(f'Request: {self.request!r}')