[Bug] pulsar-cpp-client pulsar::HTTPLookupService::handleLookupHTTPRequest coredump

### Search before asking

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

### Version

pulsar-cpp-client v2.8.3 gcc7.3.1

### Minimal reproduce step

The probability is low

### What did you expect to see?

solve this bug

### What did you see instead?

pulsar-cpp-client v2.8.3

### Anything else?

_No response_

### Are you willing to submit a PR?

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

Start at pulsar::HTTPLookupService::handleLookupHTTPRequest and reproduce the reported coredump using pulsar-cpp-client v2.8.3 with gcc 7.3.1. The issue says reproduction probability is low and provides only screenshots, so first narrow down the triggering request or state. Done means identifying the crash cause and confirming the lookup request no longer coredumps.

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