**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
dag_ids=[],
            pickle_dags=pickle_dags,
            async_mode=async_mode,
        )
        try:
            self.executor.job_id = self.id
            self.executor.start()
            self.register_signals()
            self.processor_agent.start()
            execute_start_time = timezone.utcnow()
            self._run_scheduler_loop()
            
            self.processor_agent.terminate()
            
            
            
            if self.processor_agent.all_files_processed:
                self.log.info(
                    "Deactivating DAGs that haven't been touched since %s", execute_start_time.isoformat()
                )
                models.DAG.deactivate_stale_dags(execute_start_time)
            self.executor.end()
            settings.Session.remove()  
        except Exception:  
            self.log.exception("Exception when executing SchedulerJob._run_scheduler_loop")
        finally:
            self.processor_agent.end()
            self.log.info("Exited execute loop")
    @staticmethod
    def _create_dag_file_processor(