### Apache Airflow version

2.5.1

### What happened

/calendar page give a problem, here is the capture



![屏幕截图 2023-01-30 093116](https://user-images.githubusercontent.com/19165258/215369479-9fc7de5c-f190-460c-9cf7-9ab27d8ac355.png)


### What you think should happen instead

_No response_

### How to reproduce

_No response_

### Operating System

Ubuntu 22.04.1 LTS

### Versions of Apache Airflow Providers

Distributor ID: Ubuntu
Description:    Ubuntu 22.04.1 LTS
Release:        22.04
Codename:       jammy

### Deployment

Other

### Deployment details


Distributor ID: Ubuntu
Description:    Ubuntu 22.04.1 LTS
Release:        22.04
Codename:       jammy

### Anything else

_No response_

### 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)

"""Duplicate Multiple connections"""
        for selected_conn in connections:
            new_conn_id = selected_conn.conn_id
            match = re.search(r"_copy(\d+)$", selected_conn.conn_id)
            base_conn_id = selected_conn.conn_id
            if match:
                base_conn_id = base_conn_id.split("_copy")[0]
            potential_connection_ids = [f"{base_conn_id}_copy{i}" for i in range(1, 11)]
            query = session.query(Connection.conn_id).filter(Connection.conn_id.in_(potential_connection_ids))
            found_conn_id_set = {conn_id for conn_id, in query}
            possible_conn_id_iter = (
                connection_id
                for connection_id in potential_connection_ids
                if connection_id not in found_conn_id_set
            )
            try:
                new_conn_id = next(possible_conn_id_iter)
            except StopIteration:
                flash(
                    f"Connection {new_conn_id} can't be added because it already exists, "
                    f"Please rename the existing connections",
                    "warning",
                )
            else:
                dup_conn = Connection(
                    new_conn_id,
                    selected_conn.conn_type,
                    selected_conn.description,
                    selected_conn.host,