When passing a non serializable JSON object in a trigger, I get the following error below. The logs become unavailable. 

my code:
```py
task_trigger_ad_attribution = TriggerDagRunOperator(
             task_id='trigger_ad_attribution',
             trigger_dag_id=AD_ATTRIBUTION_DAG_ID,
              conf={"message": "Triggered from display trigger",
                  'trigger_info':
                     {'dag_id':DAG_ID,
                         'now':datetime.datetime.now(),
                         },
                  'trigger_date' : '{{execution_date}}'
                  },
             )
```

```
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Python version: 3.6.9
Airflow version: 2.0.0
Node: henry-Inspiron-5566
-------------------------------------------------------------------------------
Traceback (most recent call last):
  File "/home/henry/Envs2/airflow3/lib/python3.6/site-packages/flask/app.py", line 2447, in wsgi_app
    response = self.full_dispatch_request()
  File "/home/henry/Envs2/airflow3/lib/python3.6/site-packages/flask/app.py", line 1952, in full_dispatch_request
    rv = self.handle_user_exception(e)
  File "/home/henry/Envs2/airflow3/lib/python3.6/site-packages/flask/app.py", line 1821, in handle_user_exception
    reraise(exc_type, exc_value, tb)
  File "/home/henry/Envs2/airflow3/lib/python3.6/site-packages/flask/_compat.py", line 39, in reraise
    raise value
  File "/home/henry/Envs2/airflow3/lib/python3.6/site-packages/flask/app.py", line 1950, in full_dispatch_request
    rv = self.dispatch_request()
  File "/home/henry/Envs2/airflow3/lib/python3.6/site-packages/flask/app.py", line 1936, in dispatch_request
    return self.view_functions[rule.endpoint](**req.view_args)
  File "/home/henry/Envs2/airflow3/lib/python3.6/site-packages/airflow/www/auth.py", line 34, in decorated
    return func(*args, **kwargs)
  File "/home/henry/Envs2/airflow3/lib/python3.6/site-packages/airflow/www/decorators.py", line 97, in view_func
    return f(*args, **kwargs)
  File "/home/henry/Envs2/airflow3/lib/python3.6/site-packages/airflow/www/decorators.py", line 60, in wrapper
    return f(*args, **kwargs)
  File "/home/henry/Envs2/airflow3/lib/python3.6/site-packages/airflow/www/views.py", line 1997, in tree
    data = htmlsafe_json_dumps(data, separators=(',', ':'))
  File "/home/henry/Envs2/airflow3/lib/python3.6/site-packages/jinja2/utils.py", line 614, in htmlsafe_json_dumps
    dumper(obj, **kwargs)
  File "/usr/lib/python3.6/json/__init__.py", line 238, in dumps
    **kw).encode(obj)
  File "/usr/lib/python3.6/json/encoder.py", line 199, in encode
    chunks = self.iterencode(o, _one_shot=True)
  File "/usr/lib/python3.6/json/encoder.py", line 257, in iterencode
    return _iterencode(o, 0)
  File "/usr/lib/python3.6/json/encoder.py", line 180, in default
    o.__class__.__name__)
TypeError: Object of type 'datetime' is not JSON serializable
```
airflow/operators/trigger_dagrun.py
self,
        *,
        trigger_dag_id: str,
        conf: Optional[Dict] = None,
        execution_date: Optional[Union[str, datetime.datetime]] = None,
        reset_dag_run: bool = False,
        wait_for_completion: bool = False,
        poke_interval: int = 60,
        allowed_states: Optional[List] = None,
        failed_states: Optional[List] = None,
        **kwargs,
    ) -> None:
        super().__init__(**kwargs)
        self.trigger_dag_id = trigger_dag_id
        self.conf = conf
        self.reset_dag_run = reset_dag_run
        self.wait_for_completion = wait_for_completion
        self.poke_interval = poke_interval
        self.allowed_states = allowed_states or [State.SUCCESS]
        self.failed_states = failed_states or [State.FAILED]
        if not isinstance(execution_date, (str, datetime.datetime, type(None))):
            raise TypeError(
                "Expected str or datetime.datetime type for execution_date."
                "Got {}".format(type(execution_date))
            )
        self.execution_date: Optional[datetime.datetime] = execution_date  
    def execute(self, context: Dict):