**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,
)
```
tests/jobs/test_scheduler_job.py
} == {(ti.task_id, ti.state) for ti in tis}
        for state, start_date, end_date, duration in [
            (ti.state, ti.start_date, ti.end_date, ti.duration) for ti in tis
        ]:
            if state == 'success':
                assert start_date is not None
                assert end_date is not None
                assert 0.0 == duration
            else:
                assert start_date is None
                assert end_date is None
                assert duration is None
        scheduler_job._schedule_dag_run(dr, {}, session)
        with create_session() as session:
            tis = session.query(TaskInstance).all()
        assert 5 == len(tis)
        assert {
            ('test_task_a', 'success'),
            ('test_task_b', 'success'),
            ('test_task_c', 'success'),
            ('test_task_on_execute', 'scheduled'),
            ('test_task_on_success', 'scheduled'),
        } == {(ti.task_id, ti.state) for ti in tis}
        for state, start_date, end_date, duration in [
            (ti.state, ti.start_date, ti.end_date, ti.duration) for ti in tis
        ]:
            if state == 'success':
                assert start_date is not None
                assert end_date is not None
                assert 0.0 == duration