Fail running example `examples/asyncpg_items.py`

[dotnet-7]

Describe the issue:
Run python examples/asyncpg_items.py, get error as follow：

Repro Steps:

1. Run azd init -t azure-postgres-pgvector-python.
2. Install dependices: python -m pip install -r requirements.txt.
3. Deploy the postgresql resource: azd provision.
4. Set Env: azd env get-values > .env
5. Run python examples/asyncpg_items.py.

Environment:

• Template: azure-postgres-pgvector-python.
• Azd version : azd version 1.7.0 (commit 49d6adc2efb178083f61822e6b4715258560803d)

Expected behavior:
Run python examples/asyncpg_items.py can pass.

@pamelafox , @hemarina for notification.