[Bug] MaxMessageSize might be incorrect when accessing multiple clusters

### Search before asking

- [X] I searched in the [issues](https://github.com/apache/pulsar-client-cpp/issues) and found nothing similar.

### Version

3.5.0

### Minimal reproduce step

See https://github.com/apache/pulsar/pull/22306

### What did you expect to see?

...

### What did you see instead?

...

### Anything else?

_No response_

### Are you willing to submit a PR?

- [x] I'm willing to submit a PR!

首先检查链接的 Apache Pulsar pull request 以及 3.5.0 版本中 C++ 客户端的行为。复现访问多个集群的情况，并将报告的 MaxMessageSize 与预期限制进行比较；当大小正确并且已在受影响的集群配置中完成验证时，即视为完成。

由索引模型根据 Issue 内容生成。