### Apache Airflow version

2.4.2

### What happened

Create a DAG and set the schedule parameter using a CronTriggerTimeTable instance. Enable the DAG so that there is DAG run data. Try to access the Calendar View for the DAG. An ERR_EMPTY_RESPONSE error is displayed instead of the page.

The Calendar View is accessible for other DAGs  that are using the schedule_interval set to a cron string instead.

### What you think should happen instead

The Calendar View should have been displayed.

### How to reproduce

Create a DAG and set the schedule parameter to a CronTriggerTimeTable instance. Enable the DAG and allow some DAG runs to occur. Try to access the Calender View for the DAG.

### Operating System

Red Hat Enterprise Linux 8.6

### Versions of Apache Airflow Providers

_No response_

### Deployment

Virtualenv installation

### Deployment details

Airflow 2.4.2 installed via pip with Python3.9 to venv using constraints.

### Anything else

_No response_

### Are you willing to submit PR?

- [X] 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)

"""Shows configuration."""
        raw = request.args.get("raw") == "true"
        title = "Airflow Configuration"
        subtitle = AIRFLOW_CONFIG
        expose_config = conf.get("webserver", "expose_config")
        
        
        
        if expose_config.lower() == "non-sensitive-only":
            from airflow.configuration import SENSITIVE_CONFIG_VALUES
            updater = configupdater.ConfigUpdater()
            updater.read(AIRFLOW_CONFIG)
            for sect, key in SENSITIVE_CONFIG_VALUES:
                if updater.has_option(sect, key):
                    updater[sect][key].value = "< hidden >"
            config = str(updater)
            table = [
                (section, key, str(value), source)
                for section, parameters in conf.as_dict(True, False).items()
                for key, (value, source) in parameters.items()
            ]
        elif expose_config.lower() in ["true", "t", "1"]:
            with open(AIRFLOW_CONFIG) as file:
                config = file.read()