**Apache Airflow version**: 2.0.0


**Kubernetes version (if you are using kubernetes)** (use `kubectl version`):

**Environment**:

- **Cloud provider or hardware configuration**:
- **OS** (e.g. from /etc/os-release):
- **Kernel** (e.g. `uname -a`):
- **Install tools**:
- **Others**:

**What happened**:

I have the following DAG:

```py
from datetime import datetime, timedelta

from airflow import DAG
from airflow.operators.bash_operator import BashOperator

with DAG(
    dag_id="sla_trigger",
    schedule_interval="* * * * *",
    start_date=datetime(2020, 2, 3),
) as dag:
    BashOperator(
        task_id="bash_task",
        bash_command="sleep 30",
        sla=timedelta(seconds=2),
    )

```

And in my understanding this dag should result in SLA miss every time it is triggered (every minute). However, after few minutes of running I don't see any SLA misses...

**What you expected to happen**:

I expect to see SLA if task takes longer than expected.

**How to reproduce it**:

Use the dag from above.

**Anything else we need to know**:

N/A

tests/jobs/test_scheduler_job.py
dag_id = 'test_reset_orphaned_tasks_no_orphans'
        dag = DAG(dag_id=dag_id, start_date=DEFAULT_DATE, schedule_interval='@daily')
        task_id = dag_id + '_task'
        DummyOperator(task_id=task_id, dag=dag)
        scheduler = SchedulerJob(subdir=os.devnull)
        session = settings.Session()
        session.add(scheduler)
        session.flush()
        dr1 = dag.create_dagrun(
            run_type=DagRunType.SCHEDULED,
            state=State.RUNNING,
            execution_date=DEFAULT_DATE,
            start_date=DEFAULT_DATE,
            session=session,
        )
        tis = dr1.get_task_instances(session=session)
        tis[0].state = State.RUNNING
        tis[0].queued_by_job_id = scheduler.id
        session.merge(dr1)
        session.merge(tis[0])
        session.flush()
        assert 0 == scheduler.adopt_or_reset_orphaned_tasks(session=session)
        tis[0].refresh_from_db()
        assert State.RUNNING == tis[0].state
    def test_reset_orphaned_tasks_non_running_dagruns(self):