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/cli/commands/test_jobs_command.py
clear_db_jobs()
    def tearDown(self) -> None:
        clear_db_jobs()
    def test_should_report_success_for_one_working_scheduler(self):
        with create_session() as session:
            job = SchedulerJob()
            job.state = State.RUNNING
            session.add(job)
            session.commit()
            job.heartbeat()
        with contextlib.redirect_stdout(io.StringIO()) as temp_stdout:
            jobs_command.check(self.parser.parse_args(['jobs', 'check', '--job-type', 'SchedulerJob']))
        self.assertIn("Found one alive job.", temp_stdout.getvalue())
    def test_should_report_success_for_one_working_scheduler_with_hostname(self):
        with create_session() as session:
            job = SchedulerJob()
            job.state = State.RUNNING
            job.hostname = 'HOSTNAME'
            session.add(job)
            session.commit()
            job.heartbeat()
        with contextlib.redirect_stdout(io.StringIO()) as temp_stdout:
            jobs_command.check(
                self.parser.parse_args(
                    ['jobs', 'check', '--job-type', 'SchedulerJob', '--hostname', 'HOSTNAME']
                )
            )
        self.assertIn("Found one alive job.", temp_stdout.getvalue())
    def test_should_report_success_for_ha_schedulers(self):