### Apache Airflow version

2.6.0

### What happened

Ever since we upgraded to Airflow 2.6.0 from 2.5.2, we have seen that there is a warning stating "The scheduler does not appear to be running" intermittently.

This warning goes away by simply refreshing the page. And this conforms with our findings that the scheduler has not been down at all, at any point. By calling the /health point constantly, we can get it to show an "unhealthy" status:

These are just approx. 6 seconds apart: 

```
{"metadatabase": {"status": "healthy"}, "scheduler": {"latest_scheduler_heartbeat": "2023-05-11T07:42:36.857007+00:00", "status": "healthy"}}

{"metadatabase": {"status": "healthy"}, "scheduler": {"latest_scheduler_heartbeat": "2023-05-11T07:42:42.409344+00:00", "status": "unhealthy"}}
```

This causes no operational issues, but it is misleading for end-users. What could be causing this? 

### What you think should happen instead

The warning should not be shown unless the last heartbeat was at least 30 sec earlier (default config).  

### How to reproduce

There are no concrete steps to reproduce it, but the warning appears in the UI after a few seconds of browsing around, or simply refresh the /health endpoint constantly.

### Operating System

Debian GNU/Linux 11

### Versions of Apache Airflow Providers

apache-airflow-providers-amazon==8.0.0
apache-airflow-providers-celery==3.1.0
apache-airflow-providers-cncf-kubernetes==6.1.0
apache-airflow-providers-common-sql==1.4.0
apache-airflow-providers-docker==3.6.0
apache-airflow-providers-elasticsearch==4.4.0
apache-airflow-providers-ftp==3.3.1
apache-airflow-providers-google==10.0.0
apache-airflow-providers-grpc==3.1.0
apache-airflow-providers-hashicorp==3.3.1
apache-airflow-providers-http==4.3.0
apache-airflow-providers-imap==3.1.1
apache-airflow-providers-microsoft-azure==6.0.0
apache-airflow-providers-microsoft-mssql==3.3.2
apache-airflow-providers-microsoft-psrp==2.2.0
apache-airflow-providers-microsoft-winrm==3.0.0
apache-airflow-providers-mysql==5.0.0
apache-airflow-providers-odbc==3.2.1
apache-airflow-providers-oracle==3.0.0
apache-airflow-providers-postgres==5.4.0
apache-airflow-providers-redis==3.1.0
apache-airflow-providers-sendgrid==3.1.0
apache-airflow-providers-sftp==4.2.4
apache-airflow-providers-slack==7.2.0
apache-airflow-providers-snowflake==4.0.5
apache-airflow-providers-sqlite==3.3.2
apache-airflow-providers-ssh==3.6.0


### Deployment

Official Apache Airflow Helm Chart

### Deployment details

Deployed on AKS with helm

### Anything else

None more than in the description above.

### Are you willing to submit PR?

- [ ] Yes I am willing to submit a PR!

### Code of Conduct

- [X] I agree to follow this project's [Code of Conduct](https://github.com/apache/airflow/blob/main/CODE_OF_CONDUCT.md)

#
#
#
from __future__ import annotations
from time import sleep
from typing import Callable, NoReturn
from sqlalchemy import Column, Index, Integer, String, case
from sqlalchemy.exc import OperationalError
from sqlalchemy.orm import backref, foreign, relationship
from sqlalchemy.orm.session import Session, make_transient
from airflow.compat.functools import cached_property
from airflow.configuration import conf
from airflow.exceptions import AirflowException
from airflow.executors.executor_loader import ExecutorLoader
from airflow.listeners.listener import get_listener_manager
from airflow.models.base import ID_LEN, Base
from airflow.serialization.pydantic.job import JobPydantic
from airflow.stats import Stats
from airflow.utils import timezone
from airflow.utils.helpers import convert_camel_to_snake
from airflow.utils.log.logging_mixin import LoggingMixin
from airflow.utils.net import get_hostname
from airflow.utils.platform import getuser
from airflow.utils.session import NEW_SESSION, create_session, provide_session
from airflow.utils.sqlalchemy import UtcDateTime
from airflow.utils.state import State
def _resolve_dagrun_model():