**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
dag_model = session.query(DagModel).get(dag.dag_id)
        assert dag_model.next_dagrun == DEFAULT_DATE
        job = SchedulerJob(subdir=os.devnull)
        job.executor = MockExecutor(do_update=False)
        job.processor_agent = mock.MagicMock(spec=DagFileProcessorAgent)
        
        
        job._do_scheduling(session)
        dr1 = dag.get_dagrun(DEFAULT_DATE, session)
        assert dr1 is not None
        assert dr1.state == State.RUNNING
        
        dag_model = session.query(DagModel).get(dag.dag_id)
        assert dag_model.next_dagrun == DEFAULT_DATE + timedelta(minutes=1)
        
        dr = dag.create_dagrun(
            state=State.RUNNING,
            execution_date=timezone.utcnow(),
            run_type=DagRunType.MANUAL,
            session=session,
            external_trigger=True,
        )
        assert dr is not None
        
        DAG.bulk_write_to_db([dag], session)
        
        
        dag_model = session.query(DagModel).get(dag.dag_id)
        assert dag_model.next_dagrun == DEFAULT_DATE + timedelta(minutes=1)
    def test_scheduler_create_dag_runs_check_existing_run(self):