This tests fails occasionally on mysql at least:

https://github.com/apache/airflow/pull/11555/checks?check_run_id=1260840314#step:9:1125

```
=================================== FAILURES ===================================
_____________ TestSchedulerJob.test_no_orphan_process_will_be_left _____________

self = <tests.jobs.test_scheduler_job.TestSchedulerJob testMethod=test_no_orphan_process_will_be_left>

    def test_no_orphan_process_will_be_left(self):
        empty_dir = mkdtemp()
        current_process = psutil.Process()
        old_children = current_process.children(recursive=True)
        scheduler = SchedulerJob(subdir=empty_dir,
                                 num_runs=1,
                                 executor=MockExecutor(do_update=False))
        scheduler.run()
        shutil.rmtree(empty_dir)
    
        # Remove potential noise created by previous tests.
        current_children = set(current_process.children(recursive=True)) - set(
            old_children)
>       self.assertFalse(current_children)
E       AssertionError: {psutil.Process(pid=3474, name='/usr/local/bin/', status='running', started='19:26:22')} is not false

tests/jobs/test_scheduler_job.py:871: AssertionError
```



tests/jobs/test_scheduler_job.py
session.commit()
        scheduler_job._change_state_for_tasks_failed_to_execute()  
        ti.refresh_from_db()
        assert State.SCHEDULED == ti.state
        
        session.query(TaskInstance).delete()
        session.commit()
        ti.state = State.RUNNING
        session.merge(ti)
        session.commit()
        scheduler_job._change_state_for_tasks_failed_to_execute()  
        ti.refresh_from_db()
        assert State.RUNNING == ti.state
    def test_adopt_or_reset_orphaned_tasks(self):
        session = settings.Session()
        dag = DAG(
            'test_execute_helper_reset_orphaned_tasks',
            start_date=DEFAULT_DATE,
            default_args={'owner': 'owner1'},
        )
        with dag:
            op1 = DummyOperator(task_id='op1')
        dag = SerializedDAG.from_dict(SerializedDAG.to_dict(dag))
        dag.clear()
        dr = dag.create_dagrun(
            run_type=DagRunType.SCHEDULED,
            state=State.RUNNING,
            execution_date=DEFAULT_DATE,
            start_date=DEFAULT_DATE,
            session=session,