**Apache Airflow version**:

1.10.12

**What happened**:

I created dag with dagrun_timeout=2 minutes. 

After 2 minutes dagrun is marked as failed and the next one is started, but task keeps going.

**What you expected to happen**:

Task is killed with dag run as it is done when you mark dagrun failed manually.

**How to reproduce it**:
```
dag = DAG(dag_id='platform.airflow-test',
          description='',
          schedule_interval="0 0 * * *",
          start_date=datetime(2020, 7, 1),
          max_active_runs=1,
          catchup=True,
          dagrun_timeout=timedelta(minutes=2))

run_this = BashOperator(
    task_id='run_after_loop',
    bash_command=' for((i=1;i<=600;i+=1)); do echo "Welcome $i times"; sleep 1;  done',
    dag=dag,
)
```
airflow/jobs/scheduler_job.py
self,
        file_path: str,
        pickle_dags: bool,
        dag_ids: Optional[List[str]],
        callback_requests: List[CallbackRequest],
    ):
        super().__init__()
        self._file_path = file_path
        self._pickle_dags = pickle_dags
        self._dag_ids = dag_ids
        self._callback_requests = callback_requests
        
        self._process: Optional[multiprocessing.process.BaseProcess] = None
        
        self._result: Optional[Tuple[int, int]] = None
        
        self._done = False
        
        self._start_time: Optional[datetime.datetime] = None
        
        
        self._instance_id = DagFileProcessorProcess.class_creation_counter
        self._parent_channel: Optional[MultiprocessingConnection] = None
        DagFileProcessorProcess.class_creation_counter += 1
    @property
    def file_path(self) -> str: