Azure服务总线队列发送和接收消息的测试

我想编写一个集成测试，检查 Python 脚本与 Azure 服务总线队列的连接。测试应该：

1. 向队列发送消息，
2. 确认消息已进入队列。

测试看起来像这样：

import pytest

from azure.servicebus import ServiceBusClient, ServiceBusMessage, ServiceBusSender

CONNECTION_STRING = <some connection string>
QUEUE = <queue name>


def send_message_to_service_bus(sender: ServiceBusSender, msg: str) -> None:
    message = ServiceBusMessage(msg)
    sender.send_message(message)


class TestConnectionWithQueue:
    def test_message_is_sent_to_queue_and_received(self):
        msg = "test message sent to queue"
        expected_message = ServiceBusMessage(msg)
        
        servicebus_client = ServiceBusClient.from_connection_string(conn_str=CONNECTION_STRING, logging_enable=True)
        with servicebus_client:
            sender = servicebus_client.get_queue_sender(queue_name=QUEUE)
            with sender:
                send_message_to_service_bus(sender, expected_message)
        
            receiver = servicebus_client.get_queue_receiver(queue_name=QUEUE)
            with receiver:
                messages_in_queue = receiver.receive_messages(max_message_count=10, max_wait_time=20)
        assert any(expected_message == str(actual_message) for actual_message in messages_in_queue)

测试偶尔会起作用，但通常不会。没有其他消息同时发送到队列。当我调试代码时，如果测试不起作用，变量messages_in_queue只是一个空列表。

为什么代码不能一直工作，应该怎么做才能修复它？