**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
"""Runs DAG processing in a separate process using DagFileProcessor
    :param file_path: a Python file containing Airflow DAG definitions
    :type file_path: str
    :param pickle_dags: whether to serialize the DAG objects to the DB
    :type pickle_dags: bool
    :param dag_ids: If specified, only look at these DAG ID's
    :type dag_ids: List[str]
    :param callback_requests: failure callback to execute
    :type callback_requests: List[airflow.utils.callback_requests.CallbackRequest]
    """
    
    class_creation_counter = 0
    def __init__(